docs(plugin): fix mdocs and git revision plugin integration

Author: machafer

.github/workflows/build-docs.yml

@@ -18,7 +18,7 @@ jobs:
     steps:
       - uses: actions/checkout@v3
       - name: Set up Python
-        uses: actions/setup-python@v1
+        uses: actions/setup-python@v4
         with:
           python-version: "3.8"
       - name: Capture branch and tag

.github/workflows/docs.yml

@@ -12,7 +12,7 @@ jobs:
     steps:
       - uses: actions/checkout@v3
       - name: Set up Python
-        uses: actions/setup-python@v1
+        uses: actions/setup-python@v4
         with:
           python-version: "3.8"
       - name: Capture branch and tag

mkdocs.yml

@@ -70,6 +70,7 @@ markdown_extensions:
 copyright: Copyright © 2021 Amazon Web Services
 
 plugins:
+  - git-revision-date
   - search
   - macros