Improve errors for test parameters

[ashawley]

Invalid test parameters, or mixing and matching test parameters that conflict raises an error, but it's not clear why. For example,

> jvm/testOnly org.scalacheck.util.PrettySpecification -- -n 200 -x 100
[error] Uncaught exception when running org.scalacheck.util.PrettySpecification: java.lang.IllegalArgumentException: Invalid test parameters
[error] sbt.ForkMain$ForkError: java.lang.IllegalArgumentException: Invalid test parameters
[error] 	at org.scalacheck.Test$.assertParams(Test.scala:225)
[error] 	at org.scalacheck.Test$.check(Test.scala:307)
[error] 	at org.scalacheck.ScalaCheckRunner$$anon$2.executeInternal(ScalaCheckFramework.scala:123)
[error] 	at org.scalacheck.ScalaCheckRunner$$anon$2.$anonfun$execute$11(ScalaCheckFramework.scala:113)
[error] 	at org.scalacheck.ScalaCheckRunner$$anon$2.$anonfun$execute$11$adapted(ScalaCheckFramework.scala:112)

This change would improve the diagnostics a bit. For the example above,

> jvm/testOnly org.scalacheck.util.PrettySpecification -- -n 200 -x 100
[error] Uncaught exception when running org.scalacheck.util.PrettySpecification: java.lang.IllegalArgumentException: Invalid test parameter: maxSize < minSize
[error] sbt.ForkMain$ForkError: java.lang.IllegalArgumentException: Invalid test parameter: maxSize < minSize
[error] 	at org.scalacheck.Test$.assertParams(Test.scala:225)
[error] 	at org.scalacheck.Test$.check(Test.scala:309)
[error] 	at org.scalacheck.ScalaCheckRunner$$anon$2.executeInternal(ScalaCheckFramework.scala:123)
[error] 	at org.scalacheck.ScalaCheckRunner$$anon$2.$anonfun$execute$11(ScalaCheckFramework.scala:113)
[error] 	at org.scalacheck.ScalaCheckRunner$$anon$2.$anonfun$execute$11$adapted(ScalaCheckFramework.scala:112)

[non]

This is a good idea!

Could you add interpolation to these? e.g.

Invalid test parameter: maxSize (10) < minSize (50)

[non]

Sorry I should have been clearer: I think it would be helpful if all of these messages interpolated the relevant parameters (so the author can see which value ended up getting used, not just the check that failed).

[non]

👍