Fix: Pin GTSAM version to 4.2.0 to resolve Docker build failure

[bksuh]

First of all, thank you for this repo — it made it much easier to try out Clio!

Problem

When building the Docker image, the build fails during catkin build because clio.rosinstall pulls the GTSAM develop branch, which introduces breaking changes:

• API breakage in kimera_rpgo: gtsam::LevenbergMarquardtParams no longer has a diagonalDamping member

Fix

Pinned the GTSAM version from develop to 4.2.0 in clio.rosinstall. As noted in MIT-SPARK/Kimera-RPGO#85, GTSAM 4.2a8 has been tested and works with the existing codebase. With this change, the Docker image builds successfully.

Note

This PR is mainly to bring this to your attention. Feel free to merge as-is, adjust the version, or modify the original repo directly — whichever works best for you. Thanks!