fix: add exception handling to hermes-utils.rb

[Saadnajmi]

Summary:

While working on the React Native macOS upgrade, I ran into this error while fetching hermes during pod install

Fetching podspec for `hermes-engine` from `../react-native/sdks/hermes-engine/hermes-engine.podspec`
[!] Failed to load 'hermes-engine' podspec: 
[!] Invalid `hermes-engine.podspec` file: SSL_connect returned=1 errno=0 peeraddr=52.41.8.25:443 state=error: certificate verify failed (unable to get certificate CRL).

 #  from /Users/sanajmi/Developer/react-native-macos/packages/react-native/sdks/hermes-engine/hermes-engine.podspec:26

It seemed this simply came from an exception in nightly_tarball_url, which would stop the process. This change adds a fallback so that pod install can continue.

Changelog:

[INTERNAL] [FIXED] - add exception handling to hermes-utils.rb

Test Plan:

CI should pass

[meta-codesync]

@sbuggay has imported this pull request. If you are a Meta employee, you can view this in D86225597.

[meta-codesync]

@sbuggay merged this pull request in 17d184c.

[react-native-bot]

This pull request was successfully merged by @Saadnajmi in 17d184c

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