ci: Simplify Alpine Linux 3.14 definition
ci: Simplify Alpine Linux 3.14 definition

Using the extended definition format is only necessary when
the defaults are not good enough, but that's not the case here.

Signed-off-by: Andrea Bolognani <3ada0bee826c753786fdbba72243dfba997094cf@redhat.com>
Reviewed-by: Martin Kletzander <e82f23e74d43760279ebcc505dac4ae70d5627d0@redhat.com>

olafhering/libvirt,zippy2/libvirt,olafhering/libvirt,crobinso/libvirt,libvirt/libvirt,zippy2/libvirt,zippy2/libvirt,jfehlig/libvirt,olafhering/libvirt,jfehlig/libvirt,crobinso/libvirt,libvirt/libvirt,zippy2/libvirt,libvirt/libvirt,crobinso/libvirt,libvirt/libvirt,jfehlig/libvirt,olafhering/libvirt,crobinso/libvirt,jfehlig/libvirt