test: add missing ref comments to parallel.status

PR-URL: #35896
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

test/parallel/parallel.status

@@ -5,7 +5,9 @@ prefix parallel
 # sample-test                        : PASS,FLAKY
 
 [true] # This section applies to all platforms
+# https://github.com/nodejs/node/issues/35881
 test-http2-respond-file-error-pipe-offset: PASS,FLAKY
+# https://github.com/nodejs/node/issues/35844
 test-worker-eventlooputil: PASS,FLAKY
 
 [$system==win32]
@@ -29,6 +31,7 @@ test-worker-memory: PASS,FLAKY
 test-worker-message-port-transfer-terminate: PASS,FLAKY
 
 [$system==linux]
+# https://github.com/nodejs/node/issues/35586
 test-webcrypto-encrypt-decrypt-aes: PASS,FLAKY
 
 [$system==macos]