Add -Xsuppress-deprecated-jvm-target-warning to modules compiled with 1.6

Currently this leads to an unknown argument warning, but it'll be
removed automatically on the next bootstrap.

libraries/kotlin.test/junit/build.gradle

@@ -30,12 +30,18 @@ configureSourcesJar()
 configureJavadocJar()
 
 compileKotlin {
-    kotlinOptions.freeCompilerArgs = ["-Xallow-kotlin-package"]
+    kotlinOptions.freeCompilerArgs = [
+        "-Xallow-kotlin-package",
+        "-Xsuppress-deprecated-jvm-target-warning",
+    ]
     kotlinOptions.moduleName = project.name
 }
 
 compileTestKotlin {
-    kotlinOptions.freeCompilerArgs = ["-Xallow-kotlin-package"]
+    kotlinOptions.freeCompilerArgs = [
+        "-Xallow-kotlin-package",
+        "-Xsuppress-deprecated-jvm-target-warning",
+    ]
 }
 
 configureJvmIrBackend(project)

libraries/kotlin.test/junit5/build.gradle

@@ -40,12 +40,18 @@ tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile) {
 }
 
 compileKotlin {
-    kotlinOptions.freeCompilerArgs = ["-Xallow-kotlin-package"]
+    kotlinOptions.freeCompilerArgs = [
+        "-Xallow-kotlin-package",
+        "-Xsuppress-deprecated-jvm-target-warning",
+    ]
     kotlinOptions.moduleName = project.name
 }
 
 compileTestKotlin {
-    kotlinOptions.freeCompilerArgs = ["-Xallow-kotlin-package"]
+    kotlinOptions.freeCompilerArgs = [
+        "-Xallow-kotlin-package",
+        "-Xsuppress-deprecated-jvm-target-warning",
+    ]
 }
 
 configureJvmIrBackend(project)

libraries/kotlin.test/jvm/build.gradle

@@ -41,13 +41,20 @@ configureSourcesJar()
 configureJavadocJar()
 
 compileKotlin {
-    kotlinOptions.freeCompilerArgs = ["-Xallow-kotlin-package", "-Xnormalize-constructor-calls=enable",
-                                      "-Xopt-in=kotlin.contracts.ExperimentalContracts"]
+    kotlinOptions.freeCompilerArgs = [
+        "-Xallow-kotlin-package",
+        "-Xnormalize-constructor-calls=enable",
+        "-Xopt-in=kotlin.contracts.ExperimentalContracts",
+        "-Xsuppress-deprecated-jvm-target-warning",
+    ]
     kotlinOptions.moduleName = project.archivesBaseName
 }
 
 compileTestKotlin {
-    kotlinOptions.freeCompilerArgs = ["-Xallow-kotlin-package"]
+    kotlinOptions.freeCompilerArgs = [
+        "-Xallow-kotlin-package",
+        "-Xsuppress-deprecated-jvm-target-warning",
+    ]
 }
 
 configureJvmIrBackend(project)

libraries/kotlin.test/testng/build.gradle

@@ -33,12 +33,18 @@ configureSourcesJar()
 configureJavadocJar()
 
 compileKotlin {
-    kotlinOptions.freeCompilerArgs = ["-Xallow-kotlin-package"]
+    kotlinOptions.freeCompilerArgs = [
+        "-Xallow-kotlin-package",
+        "-Xsuppress-deprecated-jvm-target-warning",
+    ]
     kotlinOptions.moduleName = project.name
 }
 
 compileTestKotlin {
-    kotlinOptions.freeCompilerArgs = ["-Xallow-kotlin-package"]
+    kotlinOptions.freeCompilerArgs = [
+        "-Xallow-kotlin-package",
+        "-Xsuppress-deprecated-jvm-target-warning",
+    ]
 }
 
 configureJvmIrBackend(project)