Temporary use old version of Doxygen (#2772)

.github/workflows/main.yml

@@ -240,7 +240,10 @@ jobs:
         uses: actions/checkout@v2
         with: { fetch-depth: 0 }
       - name: Install dependencies
-        run: do { choco install --no-progress doxygen.install graphviz.portable } until ($?)
+        run: |
+          # Temporary use old version of Doxygen https://github.com/urho3d/Urho3D/issues/2757
+          do { choco install --no-progress doxygen.install --version 1.8.20 } until ($?)
+          do { choco install --no-progress graphviz.portable } until ($?)
       - name: CMake
         run: rake cmake
       - name: Build