Install Pods with `--deployment` flag

[buschco]

Describe the Feature

In the templates .gitignore https://github.com/react-native-community/template/blob/main/template/_gitignore the Podfile.lock is not listed. So I think it should be possible to install them reproducible.

Possible Implementations

• some flag like --pod-deployment that should be defaulted to true if the command runs in a CI environment

I am happy to submit a PR if you like my suggested implementation.

[thymikee]

@cipolleschi should we consider that by default?