Fix SVR degree hyperparameter

[mfeurer]

• only active if kernel == 'poly'
• adapt the metadata to reflect this

Fixes issue #1189

[codecov]

Codecov Report

Merging #1308 (a5d7e48) into development (7364c68) will decrease coverage by 0.06%.
The diff coverage is 100.00%.

@@               Coverage Diff               @@
##           development    #1308      +/-   ##
===============================================
- Coverage        88.13%   88.07%   -0.07%     
===============================================
  Files              140      140              
  Lines            11163    11163              
===============================================
- Hits              9839     9832       -7     
- Misses            1324     1331       +7     

Impacted Files	Coverage Δ
...learn/pipeline/components/regression/libsvm_svr.py	91.46% <100.00%> (ø)
...mponents/feature_preprocessing/nystroem_sampler.py	85.29% <0.00%> (-5.89%)	⬇️
autosklearn/util/logging_.py	88.96% <0.00%> (-1.38%)	⬇️
...ine/components/classification/gradient_boosting.py	93.04% <0.00%> (-0.87%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 7364c68...a5d7e48. Read the comment docs.

[eddiebergman]

It seems this might change some test values as the meta-data is changed, leading to different configurations being used in the warm-start.