CI: Re-enable msys2 builds with environment 210515
This ticket is about re-enabling CI msys2 build that we disable (already disabled for S3_1, coming in #42035 to master) for failure with snapshot of 210515.
This ticket is about re-enabling CI msys2 build that we disable (already disabled for S3_1, coming in #42035 to master) for failure with snapshot of 210515.