Improve PointMass Reward Heatmap Script

[AdamGleave]

• Change label position to be more visible and bolded
• Tweak output size to match paper
• Also some minor improvements to PointMass divergence heatmaps

[codecov[bot]]

Codecov Report

Merging #9 into master will decrease coverage by 0.15%. The diff coverage is 75.32%.

@@            Coverage Diff             @@
##           master       #9      +/-   ##
==========================================
- Coverage   81.51%   81.35%   -0.16%     
==========================================
  Files          41       41              
  Lines        2461     2499      +38     
==========================================
+ Hits         2006     2033      +27     
- Misses        455      466      +11

Impacted Files	Coverage Δ
src/evaluating_rewards/analysis/visualize.py	83.15% <ø> (ø)	:arrow_up:
...uating_rewards/analysis/plot_divergence_heatmap.py	70.83% <60%> (+0.83%)	:arrow_up:
...luating_rewards/experiments/point_mass_analysis.py	78.12% <60.86%> (-10.52%)	:arrow_down:
src/evaluating_rewards/analysis/stylesheets.py	71.42% <66.66%> (-28.58%)	:arrow_down:
src/evaluating_rewards/analysis/plot_pm_reward.py	87.8% <93.54%> (+3.18%)	:arrow_up:

---

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 1fdf9f2...92da65b. Read the comment docs.