[dependabot] Bump ros_utilities from ef5ee62 to 6d3c8f3 (#551)

Bumps [ros_utilities](https://github.com/bdaiinstitute/ros_utilities) from `ef5ee62` to `6d3c8f3`.
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<summary>Commits</summary>
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<li><a href="https://github.com/bdaiinstitute/ros_utilities/commit/6d3c8f3e201cdfb184c6d30067e85e1964ba7919"><code>6d3c8f3</code></a> [SW-1712] Pin ubuntu version in workflows (<a href="https://redirect.github.com/bdaiinstitute/ros_utilities/issues/137">#137</a>)</li>
<li>See full diff in <a href="https://github.com/bdaiinstitute/ros_utilities/compare/ef5ee6297a0ff23283cd208e06fd583868161e4c...6d3c8f3e201cdfb184c6d30067e85e1964ba7919">compare view</a></li>
</ul>
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</details>

[SW-1712]: https://theaiinstitute.atlassian.net/browse/SW-1712?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

Signed-off-by: Katie Hughes <[email protected]>