Fix NON_EXHAUSTIVE_WHEN_STATEMENT warnings in project code

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

@@ -315,6 +315,7 @@ class NewMultiplatformIT : BaseGradleIT() {
                     IR -> {
                         groupDir.resolve(jsJarName).exists()
                     }
+                    BOTH -> {}
                 }
 
                 val metadataJarEntries = ZipFile(groupDir.resolve(metadataJarName)).entries().asSequence().map { it.name }.toSet()
@@ -1846,4 +1847,4 @@ class NewMultiplatformIT : BaseGradleIT() {
         HostManager.hostIsMac -> "macosX64"
         else -> throw AssertionError("Host ${HostManager.host} is not supported for this test")
     }
-}
+}