Tweak plot_1d_comparison

[mj-will]

Tweak nessai.plot.plot_1d_comparison to prevent an error when plotting live points with a field that does not contain any finite values.

Also, adds a colours argument to the function as a consequence of this change and raise errors if labels or colours are the wrong length.

[codecov-commenter]

Codecov Report

Merging #102 (d097681) into main (67dd26d) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #102      +/-   ##
==========================================
+ Coverage   94.31%   94.33%   +0.02%     
==========================================
  Files          39       39              
  Lines        3515     3533      +18     
==========================================
+ Hits         3315     3333      +18     
  Misses        200      200              

Flag	Coverage Δ
unittests	94.33% <100.00%> (+0.02%)	⬆️

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Impacted Files	Coverage Δ
nessai/plot.py	100.00% <100.00%> (ø)

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[mj-will]

Example of skipping a parameter with infinite values. All values for 1 are plotted, 'y' is skipped for 0 (blue).