Remove docfx as unnecessary

Author: Liudmila Molkova

.github/workflows/checks.yml

@@ -70,20 +70,6 @@ jobs:
     - name: run misspell
       run: make misspell
 
-  docfx:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - uses: actions/setup-dotnet@v1
-      with:
-        dotnet-version: 6.0.x
-
-    - name: install docfx
-      run: dotnet tool update -g docfx --version "3.0.0-*" --add-source https://docfx.pkgs.visualstudio.com/docfx/_packaging/docs-public-packages/nuget/v3/index.json
-
-    - name: run docfx
-      run: docfx build --dry-run
-
   semantic-conventions:
     runs-on: ubuntu-latest
     steps: