Fixed mission acknowledgement failure

[evan-palmer]

Checklist

• I have performed a thorough review of my code
• I have sufficiently commented my code
• The implementation follows the project style conventions
• All project unit tests are passing
• If necessary, documentation has been provided or updated to discuss the changes
• System integration tests are performed successfully
• Any new dependencies have been added to the requirements list
• Any changes that will not be completed or bugs that have been introduced have been added as issues

Changes Made

This PR resolves a bug in which pymavswarm was unable to acknowledge that goto commands were received even though there was a physical response from the command.

Associated Issues

• Closes [BUG]: goto command is not acknowledged after send #94

Files Changed

• pymavswarm/mavswarm.py: Changed acknowledgement packet that the goto command should check for
• tox.ini: Fixed envlist specification

Testing

Hardware regression tests were performed by @grantphllps (Thanks, Grant!) using the goto.py example. These tests were successful.

Issues Introduced

N/A