pipx reinstall: An exception will now be raised if package is pinned

[dukecat0]

…inned package

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

Summary of changes

pipx reinstall: An exception will now be raised if package is pinned.
Fixes #1611

Test plan

Tested by running

pipx install black
pipx pin black
pipx reinstall black
pipx unpin black
pipx reinstall black

[Gitznik]

The code looks fine to me. I'm not 100% sure we need the --unpin flag though, IMO raising an error should be enough. The user can already achieve this behavior via pipx unpin packagex && pipx reinstall packagex. pipx unpin does not error if the package is not pinned.

[dukecat0]

Sounds reasonable, let's make it simple here. :)

[Gitznik]

looks good 👍