[hotfix] Remove package by its reference

[uilianries]

Now it's possible to remove a packages based on its package reference, for example:

conan remove foobar/0.1@user/testing#f3367e0e7d170aa12abccb175fee5f97:5ab84d6acfe1f23c4fae0ab88f26e3a396351ac9

As we can't break our current behavior, [-p|--package] is still valid but when both package reference and -p have a package ID, it will be considered an error, resulting in a ConanException

I didn't use pytest, because the entire file is python unittest and I don't want to mix the things. Let's update in a next PR as enhancement.

Changelog: Fix: Make conan remove accept package reference syntax.
Docs: conan-io/docs#2198

Fixes: #6545

/cc @danimtb

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[memsharded]

Good job.

[memsharded]

I didn't use pytest, because the entire file is python unittest and I don't want to mix the things. Let's update in a next PR as enhancement.

Not a concern for me to write new tests (changing tests it is worse, because not easy to see what changed), but if you don't mind, as you prefer, sure.

[danimtb]

✔️