Do not run prepare_pods with js1 oss update-pods

Summary:
The order of following calls is irrelevant.
```
  __update_pods_and_offline_mirrors "$JS_ENGINE_JSC"
  __update_pods_and_offline_mirrors "$JS_ENGINE_HERMES"
```
If execute `__update_pods_and_offline_mirrors "$JS_ENGINE_HERMES"` last, then `prepare_pods "$JS_ENGINE_HERMES"` is redundant.

allow-large-files

Changelog:
[Internal][Changed] - Cleanup offline pod mirrors updating behaviour.

Reviewed By: cipolleschi

Differential Revision: D41346899

fbshipit-source-id: 694713330fb94561d872883a18f97869cd30cd26

packages/rn-tester/Podfile.lock

@@ -954,7 +954,7 @@ SPEC CHECKSUMS:
   FlipperKit: cbdee19bdd4e7f05472a66ce290f1b729ba3cb86
   fmt: ff9d55029c625d3757ed641535fd4a75fedc7ce9
   glog: 04b94705f318337d7ead9e6d17c019bd9b1f6b1b
-  hermes-engine: eef898075e6242f0e6b71c6dae00630dd7a35b21
+  hermes-engine: d18f5a58d912c767ed56b58821bddd685d766712
   libevent: 4049cae6c81cdb3654a443be001fb9bdceff7913
   OpenSSL-Universal: ebc357f1e6bc71fa463ccb2fe676756aff50e88c
   RCT-Folly: 424b8c9a7a0b9ab2886ffe9c3b041ef628fd4fb1