[PowerAssert] Add Gradle build tools integration tests for Power-Assert

The integration test project was copied from the sample project in
github.com/bnorm/kotlin-power-assert. Original license information has
been preserved even though commit history has not been.

^KT-65951 Fixed

license/README.md

@@ -246,6 +246,10 @@ any distributions of the tools or libraries:
              and Eclipse Distribution License - v1.0 ([license/third_party/testdata/eclipse_distribution_license.txt][eclipse-distribution])
       - Origin: javax.persistence, Copyright (c) 2008, 2017 Sun Microsystems, Oracle Corporation.
 
+ - Path: libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/powerAssertSimple
+      - License: Apache 2 ([license/third_party/power_assert_license.txt][power-assert])
+      - Origin: Copyright (C) 2020-2023 Brian Norman
+
  - Path: libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/targets/js/nodejs/Platform.kt
       - License: Apache License 2.0 ([license/third_party/gradle-node-plugin_LICENSE.txt](third_party/gradle-node-plugin_LICENSE.txt))
       - Origin: Copyright (c) 2013 node-gradle/gradle-node-plugin