Add docs team to tag list for docs configuation changes (Qiskit#9714)

This adds the current docs team to the qiskit-bot configuration to get
automatically tagged when changes to the `docs` folder are made.  For
the most part, this should just be about the documentation build itself,
which is under their umbrella, rather than the text of the API docs
which is largely generated from Terra's Python source code.

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

qiskit_bot.yaml

@@ -43,4 +43,8 @@ notifications:
         - "@kevinhartman"
     "(?!.*pulse.*)\\bvisualization\\b":
         - "@enavarro51"
+    "^docs/":
+        - "@javabster"
+        - "@HuangJunye"
+        - "@Eric-Arellano"
 always_notify: true