Update gh actions to run 3.6+

Author: timvink

.github/workflows/unittests.yml

@@ -9,7 +9,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        python-version: [3.5, 3.6, 3.7]
+        python-version: [3.6, 3.7, 3.8, 3.9]
     steps:
     - uses: actions/checkout@master
 
@@ -18,23 +18,6 @@ jobs:
       with:
         python-version: ${{ matrix.python-version }}
 
-    # https://github.com/actions/virtual-environments/issues/294
-    - name: Configure path to rc.exe for Python 3.5
-      run: |
-        function Invoke-VSDevEnvironment {
-            $vswhere = "${env:ProgramFiles(x86)}\Microsoft Visual Studio\Installer\vswhere.exe"
-            $installationPath = & $vswhere -prerelease -legacy -latest -property installationPath
-            $Command = Join-Path $installationPath "Common7\Tools\vsdevcmd.bat"
-                & "${env:COMSPEC}" /s /c "`"$Command`" -no_logo && set" | Foreach-Object {
-                if ($_ -match '^([^=]+)=(.*)') {
-                    [System.Environment]::SetEnvironmentVariable($matches[1], $matches[2])
-                }
-            }
-        }
-        Invoke-VSDevEnvironment
-        Get-Command rc.exe | Format-Table -AutoSize
-      if: matrix.os == 'windows-latest' && matrix.python-version == '3.5'
-
     - name: Install dependencies
       run: |
         pip3 install --upgrade pip
@@ -52,4 +35,5 @@ jobs:
       run: |
         git config --global user.name "Github Action"
         git config --global user.email "[email protected]"
-        pytest --cov=mkdocs_git_revision_date_localized_plugin --cov-report=xml
+        pytest --cov=mkdocs_git_revision_date_localized_plugin --cov-report=xml
+