[0.76] Drop custom source map exclusion rule

[huntie]

Summary

Cherry pick of #135 to 0.76-stable. We want to release this ASAP to fix Expo behaviour out-of-the-box.

Test plan

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Upstreaming plan

• This commit should be sent as a patch to the upstream devtools-frontend repo. I've reviewed the contribution guide.
• This commit is React Native-specific and cannot be upstreamed.