install Python3 to a known path in Windows CI

This avoids a latent problem wherein Python is installed to a directory
containing its version number and the follow on `Path` manipulation was hard
coded to Python 3.9. This would have broken as soon as Python 3.10 became
available through Chocolatey. Closes #2085. Note, I still do not understand why
the documented technique Chocolatey recommends of `refreshenv` does not work.

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index b1cf1c1d4be9048edd3061c33a1caca648feb927..429287f60d580b4e7edd5a5cdc333ab5aead7e96 100644 (file)
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -126,8 +126,8 @@ portable-source:
     script:
         - $ErrorActionPreference = "Stop"
         - $PSDefaultParameterValues['Out-File:Encoding'] = 'utf8'
-        - choco install --yes --no-progress python3
-        - $env:Path = "C:\Python39;" + $env:Path
+        - choco install --yes --no-progress --params "/InstallDir:C:\Python3" python3
+        - $env:Path = "C:\Python3;" + $env:Path
         - python --version
         - python -m pip install --requirement requirements.txt
         # Toolchain definitions