add initial Cargo.lock

[jpetrucciani]

Description of the changes
This PR adds a Cargo.lock file and removes the Cargo.lock entry from the .gitignore in order to make the build easier to reproduce

Type of change
Please select one or multiple of the following options:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Code cleanup (refactoring or improving code quality)
• Documentation update (adding or updating documentation, updating README)

Checklist:

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

Additional information
Add any other information or screenshots about the pull request here.

[jkfran]

Hi @jpetrucciani, thank you for your contribution!