[MBUILDCACHE-87] - Checksum should consider plugin dependencies

[reda-alaoui]

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[AlexanderAshitkin]

In addition to the test created, it will be nice to cover the logic with tests more cases:

• External plugin dependency of a snapshot version is also accounted for in the checksum.
• Dependencies present both as a project dependency and a plugin dependency are counted twice (adding a plugin dependency in addition to an existing project dependency changes the checksum) and vice versa

[AlexanderAshitkin]

The increased entropy could be a potential vector of regression. Though the feature looks legit and should be on by default, there should be a way to turn it off if it doesn't work as expected. Please add a configuration flag to turn it off. Ideally, it should be a per-plugin flag.

[reda-alaoui]

Oups, I forgot to add logs.

[reda-alaoui]

@AlexanderAshitkin can you take a look again?