Add support for UR30 in start_ursim.sh

[fmauch]

Resolves #192

I'll make this a draft for now, as there is no docker image supporting the UR30 available at the moment.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (914e68c) 72.09% compared to head (54c23c2) 72.09%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #193 +/- ## ======================================= Coverage 72.09% 72.09% ======================================= Files 71 71 Lines 2652 2652 Branches 337 337 ======================================= Hits 1912 1912 Misses 554 554 Partials 186 186 ```

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