Strict type Dependabot::Bundler::FileFetcher

[raj-meka]

What are you trying to accomplish?

Sorbet Implementation for Bundler FileFetcher ruby file.

Anything you want to highlight for special attention from reviewers?

Please pay attention to the fixes in the Bundler FileFetcher ruby file.

How will you know you've accomplished your goal?

The sorbet rules will fire as needed.

Checklist

• I have run the complete test suite to ensure all tests and linters pass.
• I have thoroughly tested my code changes to ensure they work as expected, including adding additional tests for new functionality.
• I have written clear and descriptive commit messages.
• I have provided a detailed description of the changes in the pull request, including the problem it addresses, how it fixes the problem, and any relevant details about the implementation.
• I have ensured that the code is well-documented and easy to understand.

[sachin-sandhu]

Approving changes.