[Core] Multi-tenancy: Job isolation & implement per job config (except for env variables) (#9500)

java/runtime/src/main/resources/ray.default.conf

@@ -29,6 +29,15 @@ ray {
     // executing tasks from different jobs. E.g. if it's set to '/tm/job_resources',
     // the path for job 123 will be '/tmp/job_resources/123'.
     resource-path: ""
+    /// The number of java worker per worker process.
+    num-java-workers-per-process: 10
+    /// The jvm options for java workers of the job.
+    jvm-options: []
+    // Environment variables to be set on worker processes.
+    worker-env {
+      // key1 : "value1"
+      // key2 : "value2"
+    }
   }
 
   // Configurations about logging.