fix: Revert muzzle plugin checks

Author: bric3

buildSrc/src/main/groovy/MuzzlePlugin.groovy

@@ -722,14 +722,23 @@ abstract class MuzzleTask extends DefaultTask {
     MuzzleDirective muzzleDirective = null
   ) {
     def workQueue
-    String javaVersion = muzzleDirective?.javaVersion ?: "8"
-    def javaLauncher = javaToolchainService.launcherFor { spec ->
-      spec.languageVersion.set(JavaLanguageVersion.of(javaVersion))
-    }.get()
-    workQueue = workerExecutor.processIsolation { spec ->
-      spec.forkOptions { fork ->
-        fork.executable = javaLauncher.executablePath
+    String javaVersion = muzzleDirective?.javaVersion
+    if (javaVersion) {
+      def javaLauncher = javaToolchainService.launcherFor { spec ->
+        spec.languageVersion.set(JavaLanguageVersion.of(javaVersion))
+      }.get()
+      // Note process isolation leaks gradle dependencies to the child process
+      // and may need additional code on muzzle plugin to filter those out
+      // See https://github.com/gradle/gradle/issues/33987
+      workQueue = workerExecutor.processIsolation { spec ->
+        spec.forkOptions { fork ->
+          fork.executable = javaLauncher.executablePath
+        }
       }
+    } else {
+      // noIsolation worker is OK for muzzle tasks as their checks will inspect classes outline
+      // and should not be impacted by the actual running JDK.
+      workQueue = workerExecutor.noIsolation()
     }
     workQueue.submit(MuzzleAction.class, parameters -> {
       parameters.buildStartedTime.set(invocationDetails.buildStartedTime)