Remove usage of JVM target 1.6 from HierarchicalMppIT

#KT-45165

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/hierarchical-mpp-multi-modules/bottom-mpp/build.gradle

@@ -15,11 +15,11 @@ kotlin {
             kotlinOptions.jvmTarget = "1.8"
         }
     }
-    jvm("jvm16") {
-        attributes { attribute(complexLibAttribute, 'jvm16') }
+    jvm("jvm9") {
+        attributes { attribute(complexLibAttribute, 'jvm9') }
 
         compilations.all {
-            kotlinOptions.jvmTarget = "1.6"
+            kotlinOptions.jvmTarget = "9"
         }
     }
     // This is for iPhone emulator
@@ -53,14 +53,14 @@ kotlin {
         }
 
         // creating a diamond
-        jvmJavaJvm16Main {
+        jvmJavaJvm9Main {
             dependsOn commonMain
             dependencies {
                 api project(":api-jvm")
             }
         }
 
-        jvmJavaJvm16Test {
+        jvmJavaJvm9Test {
             dependsOn commonTest
         }
 
@@ -76,30 +76,30 @@ kotlin {
         }
 
         // setting up the targets source sets
-        jvm16Main {
+        jvm9Main {
             dependencies { }
 
             // connecting to the diamond
-            dependsOn jvmJavaJvm16Main
+            dependsOn jvmJavaJvm9Main
         }
-        jvm16Test {
+        jvm9Test {
             dependencies { }
 
             // connecting to the diamond
-            dependsOn jvmJavaJvm16Test
+            dependsOn jvmJavaJvm9Test
         }
         jvmWithJavaMain {
             dependencies {  }
 
             // connecting to the diamond
-            dependsOn jvmJavaJvm16Main
+            dependsOn jvmJavaJvm9Main
             dependsOn jvmWithJavaiOSMain
         }
         jvmWithJavaTest {
             dependencies { }
 
             // connecting to the diamond
-            dependsOn jvmJavaJvm16Test
+            dependsOn jvmJavaJvm9Test
             dependsOn jvmWithJavaiOSTest
         }
 

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/hierarchical-mpp-multi-modules/bottom-mpp/src/jvm9Main/kotlin/transitiveStory/midActual/commonSource/SomeMPPInTheCommon.kt

@@ -10,4 +10,4 @@ actual open class SomeMPPInTheCommon actual constructor() {
 
 }
 
-actual val sourceSetName: String = "jvm16Main"
+actual val sourceSetName: String = "jvm9Main"