Bump docfx to 2.77.0 (#356)

Author: roji

.github/workflows/build-documentation.yml

@@ -59,7 +59,7 @@ jobs:
     # You can get the docfx default template via the following command: docfx template export default
     # This will put the default template folder into a directory called _exported_templates
     - name: Get docfx
-      run: dotnet tool install --version 2.61.0 -g docfx
+      run: dotnet tool install --version 2.77.0 -g docfx
 
     - name: Build docs
       run: docfx