Remove EffectCompat from Test signature.

[zainab-ali]

The EffectCompat typeclass combines Async and Parallel instances, and has a few overridable helper functions.

In particular, the realTimeMillis function is used to override the clock time when testing.

EffectCompat is present in the Test class signature. Users who implement their own SharedResourceSuite must construct a Test, so must have access to an EffectCompat. This can be confusing.

This PR replaces EffectCompat implicit with cats-effect typeclasses. The EffectCompat instance is deconstructed into Clock, Defer and Concurrent, such that the Clock can be replaced during testing.