Introduce a new env variable to allow spaces in home path

[Gitznik]

• I have added a news fragment under changelog.d/ (if the patch affects the end users)

Summary of changes

Introduces an environment variable to silence the warning for having a space in the pipx home path.

Improves the docs on how to troubleshoot the warning and move the pipx installation location in general. This makes the discussion I created a while ago redundant.

Resolves #1320

Test plan

Tested by running

nox -s tests-3.8 -- -k test_environment

[Gitznik]

@huxuan if you have the time, could you please verify that the windows example for moving the pipx install location actually works? Or maybe even translate it to powershell?

[huxuan]

@huxuan if you have the time, could you please verify that the windows example for moving the pipx install location actually works? Or maybe even translate it to powershell?

Gotcha, will take a look later.

[huxuan]

Could you please verify that the windows example for moving the pipx install location actually works? Or maybe even translate it to powershell?

Verified and translated! PTAL

[Gitznik]

Sorry had to add just one small change to make sure spaces in the paths are not a problem when using bash.

[huxuan]

Sorry had to add just one small change to make sure spaces in the paths are not a problem when using bash.

looks like the double quotes are also needed for the dirs and $NEW_LOCATION in powershell to work with spaces in paths.