feat(bzlmod): mark lock_import and lock_repos as reproducible

[betaboon]

MODULE.bazel.lock also contains all the repos created by lock_import and lock_repos.
This makes the file extremely big (>1MB in our monorepo).

Since bazel 7.1.1 extension_metadata allows marking an extension as being reproducible.

Some more background:

• MODULE.bazel.lock file "reads through" already-locked package manager bazelbuild/bazel#20272
• [bzlmod] Mark npm extension as reproducible aspect-build/rules_js#1541
• refactor: Mark internal and python extension as reproducible bazelbuild/rules_python#1892
• https://bazel.build/rules/lib/builtins/module_ctx#extension_metadata

[jvolkman]

Thanks!