Prepare for release 0.3.0

[agalbachicar]

🎉 New feature

Prepare for release 0.3.0

Summary

Depends on:

• 279

• https://github.com/maliput/maliput/pull/630 and the posterior bazel release.

Test it

N/A

Checklist

• [x] Signed all commits for DCO
• [ ] Added tests
• [ ] Added example and/or tutorial
• [ ] Updated documentation (as needed)
• [ ] Updated migration guide (as needed)
• [ ] Consider updating Python bindings (if it affects the public API)

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[agalbachicar]

TSAN Errors point to drake's code.