Update discipline-scalatest

[travisbrown]

Okay, trying this again, with 1.0.0-RC4.

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Update: the NPEs were because of an initialization issue in cats.kernel.laws.Test, which was happening because the implicit PropertyCheckConfiguration is now being resolved where checkAll is called instead of in discipline-scalatest (where previously it always used generatorDrivenConfig).

Unfortunately ScalaTest's org.scalatest.prop.Configuration defines generatorDrivenConfig as a val, so we can't just slap a lazy on the override. Instead I've added a configuration class that makes the initialization work out right.

This is the only place this issue showed up either here or in Circe, which I've also updated to discipline-scalatest 1.0.0-RC4, and I think it's likely to be rare—it's only showing up here because of the kind of unusual arrangement of Scala-version-specific tests.

I also think the new behavior is the correct behavior. If the user was writing tests in terms of check directly, the implicit configuration would be resolved at the point where they call check—it wouldn't just use generatorDrivenConfig automatically. In my view our checkAll should do the same.

(I'll note the issue in the final 1.0.0 release notes.)

[travisbrown]

Will look at the 2.13 failures in the morning.

[codecov-io]

Codecov Report

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@@            Coverage Diff            @@
##             master    #3259   +/-   ##
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  Coverage          ?   93.41%           
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  Hits              ?     6764           
  Misses            ?      477           
  Partials          ?        0

Flag	Coverage Δ
#scala_version_212	93.41% <ø> (?)

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