Fix docs GitHub deployment (#202)

* Update to actions/deploy-pages@v4

* Remove unsafe_html linter rule

* [REVERT THIS] trigger CI for testing

* Revert "[REVERT THIS] trigger CI for testing"

Author: solid-illiaaihistov

.github/workflows/gh-pages-deploy.yaml

@@ -87,4 +87,4 @@ jobs:
 
       - name: Deploy to GitHub Pages
         id: deployment
-        uses: actions/deploy-pages@v2
+        uses: actions/deploy-pages@v4

lib/analysis_options.yaml

@@ -272,7 +272,6 @@ linter:
     - unnecessary_this
     - unnecessary_to_list_in_spreads
     - unrelated_type_equality_checks
-    - unsafe_html
     - use_build_context_synchronously
     - use_colored_box
     - use_decorated_box