Fix memory leak and assertion bug

- Fix assertion in spock_worker.c
   Changed 'Assert(MySpockWorker->proc = MyProc)' to use '=='

- Fix memory leak in spock_apply_heap.c
  Free remotetuple after reporting conflict

Author: rasifr

src/spock_apply_heap.c

@@ -1203,6 +1203,7 @@ spock_apply_heap_delete(SpockRelation *rel, SpockTupleData *oldtup)
 							  remotetuple, NULL, SpockResolution_Skip,
 							  InvalidTransactionId, false, InvalidRepOriginId,
 							  (TimestampTz) 0, edata->targetRel->idxoid);
+		heap_freetuple(remotetuple);
 	}
 
 	/* Cleanup. */

src/spock_worker.c

@@ -427,7 +427,7 @@ spock_worker_detach(bool crash)
 
 	LWLockAcquire(SpockCtx->lock, LW_EXCLUSIVE);
 
-	Assert(MySpockWorker->proc = MyProc);
+	Assert(MySpockWorker->proc == MyProc);
 	Assert(MySpockWorker->generation == MySpockWorkerGeneration);
 	MySpockWorker->proc = NULL;