Bug fixes:
- Do not fail Action when the number of data points to be plotted in a single graph grows beyond 5000 (also see #52).
- Do not fail Action when no forks exist (also see #49).
Data handling:
- Make the top-N plots for referrers and pages less busy: show the top 7 instead of top 10 and downsample to one data point per five days if the total number of samples would otherwise grow beyond 3000.
Misc:
- Log output: improved debuggability.
- Conservative dependency update; new base image.
Testing: better coverage of entrypoint.sh logic in CI, better debuggability of bats-based CLI tests.