Docker images - no postgis/mysql image for linux/arm64 (e.g. Apple M1)

[jatcwang]

• There's currently no linux/arm64 images for postgis nor mysql
• For MySQL we can switch to bitnami/mysql, but there's no alternative for postgis that I can find at the moment. Official postgis ARM image still in the works

[matsluni]

I successfully could run the tests locally on my M1 following the suggestion to create the docker image for postgis locally and use the bitnami/mysql image. (I further needed to sbt -Duser.timezone=UTC test due to some daylight saving time change recently).