front: fix bug lpv color when selecting a speed section tag

[clarani]

closes #5287

I fixed the color of the PSL when you select a speedLimitTag, but found a new bug (backend #6623): if you select a speedLimitTag and the PSL does not have it, the PSL disappear but not its signs !

Here with a correct speedLimitTag:

[codecov]

Codecov Report

Attention: 7 lines in your changes are missing coverage. Please review.

Comparison is base (630fdc7) 27.89% compared to head (d3241b0) 17.60%.
Report is 2 commits behind head on dev.

Files	Patch %	Lines
front/src/common/Map/Layers/GeoJSONs.tsx	0.00%	3 Missing ⚠️
front/src/common/Map/Layers/SpeedLimits.tsx	0.00%	2 Missing ⚠️
...ront/src/common/Map/Layers/extensions/SNCF/PSL.tsx	0.00%	2 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##                dev    #6622       +/-   ##
=============================================
- Coverage     27.89%   17.60%   -10.29%     
  Complexity     2175     2175               
=============================================
  Files          1042      890      -152     
  Lines        127870   105065    -22805     
  Branches       2601     2605        +4     
=============================================
- Hits          35667    18496    -17171     
+ Misses        90684    85050     -5634     
  Partials       1519     1519               

Flag	Coverage Δ
core	79.36% <ø> (-0.26%)	⬇️
editoast	?
front	8.42% <0.00%> (+<0.01%)	⬆️
gateway	2.50% <ø> (ø)
railjson_generator	87.25% <ø> (ø)
tests	81.95% <ø> (ø)

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[Math-R]

lgtm