Move tests for SD inference variant pipelines into their own modules

[DN6]

What does this PR do?

Realised that when we moved the SD inference variant pipelines out of the SD module, we didn't move the corresponding tests for these pipelines out of the SD module. This PR

1. Moves all SD inference variant pipelines (GLIGEN, SD K Diffusion, etc) into their own testing modules and removes tests for deprecated pipelines (SD Paradigms, Cycle Diffusion, etc)

2. Add tests for Adapter pipelines into the list of pipelines we always test.

This should speed up the SD tests.

Fixes # (issue)

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[patrickvonplaten]

Nice!