Some plots have legend keys missing (Provinces)

[pmdscully]

• https://github.com/djay/covidthailand/wiki/cases_prov_increasing_30d.png
• https://github.com/djay/covidthailand/wiki/cases_prov_top_30d.png
• https://raw.githubusercontent.com/wiki/djay/covidthailand/deaths_by_area_3.png
• https://github.com/djay/covidthailand/wiki/vac_top5_full_3.png

[pmdscully]

Looks good. Thanks @djay 👍