Don't fail the build if verification fails against a pending pact.

[kflorence]

Fixes #51

This also includes the sbt-ide-settings plugin and configures the project so that when it is imported into the IntelliJ IDE it will exclude Scala 2.12 and Java 8 dependencies and projects. This prevents classpath conflicts (e.g. the same classes existing in 4 different contexts) and allows for a normal development experience (including the ability to run and debug tests from the IDE).

[kflorence]

Examples of test output.

MUnit

pact4s.munit.PendingPactVerificationTestSuite:
  + pending pact failure should be skipped 0.275s
[info] Passed: Total 1, Failed 0, Errors 0, Passed 1
[success] Total time: 5 s, completed Sep 11, 2021, 5:28:05 PM

Looks like MUnit doesn't log anything when a test is skipped, just marks it as passed. Maybe this is a common/okay expectation for that library? If not, we could add some logs ourselves, but it seems strange that the library wouldn't do that itself.

ScalaTest

[info] PendingPactVerificationTestSuite:
[info] pending pact failure
[info] - should be skipped !!! CANCELED !!!
[info]   Verification failed [PENDING]: "description" (PendingPactVerificationTestSuite.scala:6)
[info] Run completed in 3 seconds, 86 milliseconds.
[info] Total number of tests run: 0
[info] Suites: completed 1, aborted 0
[info] Tests: succeeded 0, failed 0, canceled 1, ignored 0, pending 0
[info] No tests were executed.
[success] Total time: 8 s, completed Sep 11, 2021, 5:28:38 PM

Weaver

[info] pact4s.weaver.PendingPactVerificationTestSuite
[info] - pending pact failure should be skipped 253ms !!! CANCELLED !!!
[info]   Verification failed [PENDING]: "description" (PendingPactVerificationTestSuite.scala:7)
[info] Passed: Total 0, Failed 0, Errors 0, Passed 0, Canceled 1
[success] Total time: 9 s, completed Sep 11, 2021, 5:33:16 PM