DOC: config: Add missing actions in "tcp-request session" documentation

set-src/set-src-port and set-dst/set-dst-port actions were not listed in the
documentation of "tcp-request session".

This patch may be backported to all stable versions.

doc/configuration.txt

@@ -12492,6 +12492,10 @@ tcp-request session <action> [{if | unless} <condition>]
     - sc-inc-gpc0(<sc-id>)
     - sc-inc-gpc1(<sc-id>)
     - sc-set-gpt0(<sc-id>) { <int> | <expr> }
+    - set-dst <expr>
+    - set-dst-port <expr>
+    - set-src <expr>
+    - set-src-port <expr>
     - set-var(<var-name>) <expr>
     - unset-var(<var-name>)
     - silent-drop