Fix flaky transmission_interface tests by making them deterministic. (backport #1665)

[mergify]

Fixes #1555

The transmission_interface tests would give non deterministic spurious failures. The non determinism was because tests were randomly generated using the system time to seed the random number generator. The spurious failures were due to occasionally occurring tiny rounding errors from floating point math.

By seeding the random number generator the tests become deterministic and we avoid the spurious failures.
Additionally, changing the order of some of the multiplications seems to reduce the rounding error.

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---

This is an automatic backport of pull request #1665 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of ace8416 has failed:

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Changes to be committed:
	modified:   transmission_interface/include/transmission_interface/four_bar_linkage_transmission.hpp

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   transmission_interface/test/random_generator_utils.hpp

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.98%. Comparing base (c04a16f) to head (2445d29).
Report is 13 commits behind head on humble.

Additional details and impacted files

@@            Coverage Diff             @@
##           humble    #1670      +/-   ##
==========================================
- Coverage   87.00%   86.98%   -0.02%     
==========================================
  Files          97       97              
  Lines        7505     7509       +4     
  Branches      677      677              
==========================================
+ Hits         6530     6532       +2     
- Misses        688      690       +2     
  Partials      287      287              

Flag	Coverage Δ
unittests	86.98% <100.00%> (-0.02%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
...ission_interface/four_bar_linkage_transmission.hpp	78.57% <100.00%> (ø)
...smission_interface/test/random_generator_utils.hpp	100.00% <100.00%> (ø)

... and 1 file with indirect coverage changes