Fixes for v234 release bugs

[LakSenanayaka]

This PR fixes the issues in importing dependancies in git_submodules and common, our CI caught during the building of https://github.com/dependabot/dependabot-core/releases/tag/v0.234.0 release. These issues exist since https://github.com/dependabot/dependabot-core/releases/tag/v0.233.0 as well.

To recreate the issue,
docker run --pull never --env CI=true --env RAISE_ON_WARNINGS=true --env SUITE_NAME=git_submodules --rm ghcr.io/dependabot/dependabot-updater-gitsubmodule bash -c "cd /home/dependabot/git_submodules && ./script/ci-test"

This PR fixes issues like,

An error occurred while loading ./spec/dependabot/dependency_group_spec.rb.
Failure/Error: extend T::Sig

NameError:
uninitialized constant WildcardMatcher::T
extend T::Sig

Failures:

1. Dependabot::GitSubmodules::UpdateChecker#can_update? given an outdated dependency
   Failure/Error: subject { checker.can_update?(requirements_to_unlock: :own) }

   RuntimeError:
   Unsupported package_manager submodules

[annettejanewilson]

Just to add - we think we only saw this on our CI because it runs on a 32 core machine. TurboTests distributes the tests evenly across one process per core, so if the number of cores is high a lot of the tests run in isolation. These missing require issues are easily masked if some other test already caused the module to be loaded.

[deivid-rodriguez]

Thanks for your fixes!