84b1bf99c6
- The implementation of `sq cert list` tried to parse the
pattern. To do so, it relied on type inference to determine how
to parse it. The type was inferred from the type of the `cert`
parameter to `authenticate`. In
2e17dec9adccb571a5474ed487f3705b5fe9ddf8, the type of the `cert`
parameter changed from `KeyHandle` to `Cert`. `Cert` has a
`Parse` implementation so the type system didn't detect anything
wrong. However, we were now trying to parse the pattern as a
`Cert` instead of a `KeyHandle`, which would fail for key handles.
- Fix it, and add some tests for `sq cert list`.