test "export" fix for MESA openGL

Author: jlarsen-usgs

.github/workflows/test.yaml

@@ -81,10 +81,11 @@ jobs:
       if: runner.os == 'Windows'
       shell: pwsh
       run: |
-        Set-StrictMode -Version 1.30
+        Set-StrictMode -Version Latest
         $ErrorActionPreference = "Stop"
         $PSDefaultParameterValues['*:ErrorAction']='Stop'
         powershell .github/install_opengl.ps1
+        export MESA_GL_VERSION_OVERRIDE=3.3
 
     - name: Run tests
       shell: bash -l {0}