Do not convert java libraries with core_platform

Test: go bp2build tests
Change-Id: I2769c0d589c304caeb24a8ecba38a4a5ee6c63e5

bp2build/java_library_conversion_test.go

@@ -1046,3 +1046,14 @@ filegroup {
 		ctx.RegisterModuleType("filegroup", android.FileGroupFactory)
 	})
 }
+
+func TestJavaSdkVersionCorePlatformDoesNotConvert(t *testing.T) {
+	runJavaLibraryTestCase(t, Bp2buildTestCase{
+		Blueprint: `java_library {
+    name: "java-lib-1",
+    sdk_version: "core_platform",
+    bazel_module: { bp2build_available: true },
+}`,
+		ExpectedBazelTargets: []string{},
+	})
+}