request: Add option to enforce lockfile in bootstrap

[spydon]

Is there an existing feature request for this?

• I have searched the existing issues.

Command

melos bootstrap --enforce-lockfile

Description

When running pub get in the pipeline doing builds you want to use pub get --enforce-lockfile so that you can know what versions a specific build uses.

Reasoning

Without this we can't troubleshoot builds properly since we can't know which exact versions that were used to build a specific version.

Additional context and comments

https://dart.dev/tools/pub/cmd/pub-get#--enforce-lockfile