Fix: Start Lightning App on Cloud if Repo Begins With Name "Lightning"

[rlizzo]

What does this PR do?

Ensure that if a repository starts with the name "lightning" that it can actually be packaged and run on the cloud. This was occurring due to not checking if the package is installed in editable mode or not. if it is not installed in editable mode, do not package the source :)

Fixes #13942
Fixes #13913

Note for Reviewers: I am having trouble figuring out how to test this. One option would be to completely mock out the _PACKAGE_ROOT variable, but this does not seem like a particularly useful test to actually ensure functionality? Looking for input here.

Does your PR introduce any breaking changes? If yes, please list them.

None

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cc @Borda

[tchaton]

LGTM !

[lantiga]

Let's get this merged and released asap

@tchaton @Borda