Do not raise when accessing the metadata of editable packages

[danimtb]

Changelog: Bugfix: Do not raise when accessing the metadata of editable packages
Docs: omit

• Refer to the issue that supports this Pull Request: closes conan remote remove fails with editable packages #5424
• If the issue has missing info, explain the purpose/use case/pain/need that covers this Pull Request.
• I've read the Contributing guide.
• I've followed the PEP8 style guides for Python code.
• I've opened another PR in the Conan docs repo to the develop branch, documenting this one.

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[lasote]

I think this doesn't solve the issue, just the crash, but the remote won't be removed for the editable reference (has to be checked in the test). I understand from the latest comment of @memsharded that the idea is to cheat the cache to consider all packages "cache" packages, but only temporary. But anyway, the remove references have to be cleaned.

[danimtb]

ok, now I got it. The last conclusion describing the implementation was not clear to me on what to do. Thanks for the clarification.

[SSE4]

is it possible to exract method? similar code repeats 5 times

[danimtb]

IMO that should be done in a refactor PR, not in this one. I don't refuse to make the changes here but I would like to wait for other reviews before. Thanks!

[SSE4]

okay

[jgsogo]

I would put this new contextmanager closer to the EditablePackages::override function.

...and I would suggest (for a different PR, once this one is done) merging both functions into a context manager that accepts an argument with the dictionary to use (the overriding one for the workspaces, and an empty one for this use case).