Allow excluding Kotlin source sets from transformation

sample/build.gradle.kts

@@ -66,4 +66,10 @@ configure<com.bnorm.power.PowerAssertGradleExtension> {
     "com.bnorm.power.assert",
     "com.bnorm.power.dbg"
   )
+  excludedSourceSets = listOf(
+    "commonMain",
+    "jvmMain",
+    "jsMain",
+    "nativeMain"
+  )
 }

sample/src/commonMain/kotlin/com/bnorm/power/Person.kt

@@ -20,6 +20,11 @@ data class Person(
   val firstName: String,
   val lastName: String,
 ) {
+  init {
+    require(firstName.isNotBlank())
+    require(lastName.isNotBlank())
+  }
+
   companion object {
     val UNKNOWN = listOf(Person("John", "Doe"), Person("Jane", "Doe"))
     override fun toString() = "Person.Companion"

sample/src/commonTest/kotlin/com/bnorm/power/PowerAssertTest.kt

@@ -63,6 +63,15 @@ class PowerAssertTest {
     )
   }
 
+  @Test
+  fun excludedRequire() {
+    val error = assertFailsWith<IllegalArgumentException> { Person("", "") }
+    assertEquals(
+      actual = error.message,
+      expected = "Failed requirement."
+    )
+  }
+
   @Test
   fun softAssert() {
     val unknown: List<Person>? = Person.UNKNOWN