[JPS] Ignore classpath from facets to exclude jars from gradle build

Reimport after `./gradlew build` adds jars from gradle's `build/libs` to facet's classpath. That causes problems with JPS build, because it doesn't see changes in out folder, but see unchanged jar, so changes don't apply.

#KT-51873 Fixed

Merge-request: KT-MR-6018
Merged-by: Aleksei Cherepanov <aleksei.cherepanov@jetbrains.com>

jps/jps-plugin/testData/general/BuildAfterGdwBuild/module2/src/Derived.kt

@@ -0,0 +1,9 @@
+class Derived: Base() {
+    override fun doSmth() {
+        println("doSmth")
+    }
+
+    override fun doSmthElse() {
+        println("doSmthElse")
+    }
+}