gitlab: switch to using 'pip' for package installation

The distutils/setuptools 'install' command is deprecated in favour of
'pip', and with recent versiosn, using it will create a bad install
that triggers a traceback on all future use of setuptools:

Traceback (most recent call last):
  File "/builds/berrange/libvirt-python/setup.py", line 328, in <module>
    setup(name = 'libvirt-python',
  File "/usr/lib/python3.10/site-packages/setuptools/__init__.py", line 154, in setup
    _install_setup_requires(attrs)
  File "/usr/lib/python3.10/site-packages/setuptools/__init__.py", line 143, in _install_setup_requires
    dist = MinimalDistribution(attrs)
  File "/usr/lib/python3.10/site-packages/setuptools/__init__.py", line 135, in __init__
    super().__init__(filtered)
  File "/usr/lib/python3.10/site-packages/setuptools/dist.py", line 456, in __init__
    for ep in metadata.entry_points(group='distutils.setup_keywords'):
  File "/usr/lib64/python3.10/importlib/metadata/__init__.py", line 1009, in entry_points
    return SelectableGroups.load(eps).select(**params)
  File "/usr/lib64/python3.10/importlib/metadata/__init__.py", line 459, in load
    ordered = sorted(eps, key=by_group)
  File "/usr/lib64/python3.10/importlib/metadata/__init__.py", line 1006, in <genexpr>
    eps = itertools.chain.from_iterable(
  File "/usr/lib64/python3.10/importlib/metadata/_itertools.py", line 16, in unique_everseen
    k = key(element)
  File "/usr/lib64/python3.10/importlib/metadata/__init__.py", line 941, in _normalized_name
    return self._name_from_stem(stem) or super()._normalized_name
  File "/usr/lib64/python3.10/importlib/metadata/__init__.py", line 622, in _normalized_name
    return Prepared.normalize(self.name)
  File "/usr/lib64/python3.10/importlib/metadata/__init__.py", line 871, in normalize
    return re.sub(r"[-_.]+", "-", name).lower().replace('-', '_')
  File "/usr/lib64/python3.10/re.py", line 209, in sub
    return _compile(pattern, flags).sub(repl, string, count)

This is certainly a bug in distutils/setuptools, but given the
'install' command is deprecated, instead of waiting for a fix,
just switch to the recommend 'pip install .' command.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

.gitlab-ci.yml

@@ -28,7 +28,7 @@ stages:
     - ninja -C build install
     - popd
     - $PYTHON setup.py build
-    - $PYTHON setup.py install
+    - $PYTHON -m pip install .
     - $PYTHON setup.py test
     - $PYTHON setup.py sdist
     - if test -x /usr/bin/rpmbuild && test "$RPM" != "skip" ; then rpmbuild --nodeps -ta dist/libvirt-python*tar.gz ; fi
@@ -40,7 +40,7 @@ stages:
     - export CFLAGS="-Werror"
   script:
     - $PYTHON setup.py build
-    - $PYTHON setup.py install
+    - $PYTHON -m pip install .
     - $PYTHON setup.py test
     - $PYTHON setup.py sdist
     - if test -x /usr/bin/rpmbuild && test "$RPM" != "skip" ; then rpmbuild --nodeps -ta dist/libvirt-python*tar.gz ; fi

ci/containers/centos-stream-8.Dockerfile

@@ -37,6 +37,7 @@ RUN dnf update -y && \
         python3-devel \
         python3-docutils \
         python3-lxml \
+        python3-pip \
         python3-pytest \
         python3-setuptools \
         rpcgen \

ci/containers/debian-10.Dockerfile

@@ -21,6 +21,7 @@ RUN export DEBIAN_FRONTEND=noninteractive && \
             python3 \
             python3-dev \
             python3-lxml \
+            python3-pip \
             python3-pytest \
             python3-setuptools && \
     eatmydata apt-get autoremove -y && \

ci/containers/debian-sid.Dockerfile

@@ -21,6 +21,7 @@ RUN export DEBIAN_FRONTEND=noninteractive && \
             python3 \
             python3-dev \
             python3-lxml \
+            python3-pip \
             python3-pytest \
             python3-setuptools && \
     eatmydata apt-get autoremove -y && \

ci/containers/fedora-34.Dockerfile

@@ -28,6 +28,7 @@ exec "$@"' > /usr/bin/nosync && \
         python3 \
         python3-devel \
         python3-lxml \
+        python3-pip \
         python3-pytest \
         python3-setuptools \
         rpm-build && \

ci/containers/fedora-35.Dockerfile

@@ -28,6 +28,7 @@ exec "$@"' > /usr/bin/nosync && \
         python3 \
         python3-devel \
         python3-lxml \
+        python3-pip \
         python3-pytest \
         python3-setuptools \
         rpm-build && \

ci/containers/fedora-rawhide.Dockerfile

@@ -29,6 +29,7 @@ exec "$@"' > /usr/bin/nosync && \
         python3 \
         python3-devel \
         python3-lxml \
+        python3-pip \
         python3-pytest \
         python3-setuptools \
         rpm-build && \

ci/containers/opensuse-leap-152.Dockerfile

@@ -18,6 +18,7 @@ RUN zypper update -y && \
            python3-base \
            python3-devel \
            python3-lxml \
+           python3-pip \
            python3-pytest \
            python3-setuptools \
            rpm-build && \

ci/containers/opensuse-tumbleweed.Dockerfile

@@ -18,6 +18,7 @@ RUN zypper dist-upgrade -y && \
            python3-base \
            python3-devel \
            python3-lxml \
+           python3-pip \
            python3-pytest \
            python3-setuptools \
            rpm-build && \

ci/containers/ubuntu-1804.Dockerfile

@@ -21,6 +21,7 @@ RUN export DEBIAN_FRONTEND=noninteractive && \
             python3 \
             python3-dev \
             python3-lxml \
+            python3-pip \
             python3-pytest \
             python3-setuptools && \
     eatmydata apt-get autoremove -y && \

ci/containers/ubuntu-2004.Dockerfile

@@ -21,6 +21,7 @@ RUN export DEBIAN_FRONTEND=noninteractive && \
             python3 \
             python3-dev \
             python3-lxml \
+            python3-pip \
             python3-pytest \
             python3-setuptools && \
     eatmydata apt-get autoremove -y && \