Run tests only for unique gradle versions

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/kotlin/org/jetbrains/kotlin/gradle/testbase/KGPBaseTest.kt

@@ -107,7 +107,8 @@ abstract class KGPBaseTest {
                 }
             }
 
-            return sequenceOf(minGradleVersion, *additionalGradleVersions.toTypedArray(), maxGradleVersion)
+            return setOf(minGradleVersion, *additionalGradleVersions.toTypedArray(), maxGradleVersion)
+                .asSequence()
                 .map { Arguments.of(it) }
                 .asStream()
         }