1.9.12.1 "Keep Moving"

This release improves Android compatibility again, while updating Gradle to 6.7.1 (and several third-party dependencies as well). It fixes a bug where Java 15 couldn't be selected as a version in the Advanced tab; now it allows from 7 to 16 in case Java 16 comes out before the next release. It defaults to using libGDX 1.9.12 but should work with lower versions as well.

EDIT: the first build of this release was made with Java 15, and no target set, so it would have needed Java 15 to run. All other versions have been built with Java 8, and so need any version 8 or higher, so now the JAR here has been rebuilt with Java 8, checked that it runs on 8 and 15, and uploaded again (same name).