Added command to install mkdocs

Author: VedantParanjape

.github/workflows/mkdocs-build.yml

@@ -19,6 +19,11 @@ jobs:
         with:
           python-version: '3.x'
 
+      - name: Install mkdocs
+        run: |
+          python -m pip install --upgrade pip
+          pip install mkdocs
+
       - name: Deploy
         run: |
           git pull