Measure network RTT between Thunderscope and Thunderloop

[Andrewyx]

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Description

Adds real-time round-trip time widget to the Robot Diagnostics tool.

Testing Done

• [ ] Field Testing

Resolved Issues

Resolves #3120

Length Justification and Key Files to Review

Review Checklist

It is the reviewers responsibility to also make sure every item here has been covered

• [ ] Function & Class comments: All function definitions (usually in the .h file) should have a javadoc style comment at the start of them. For examples, see the functions defined in thunderbots/software/geom. Similarly, all classes should have an associated Javadoc comment explaining the purpose of the class.
• [ ] Remove all commented out code
• [ ] Remove extra print statements: for example, those just used for testing
• [ ] Resolve all TODO's: All TODO (or similar) statements should either be completed or associated with a github issue