Drop Release label in favor of OSBS release_bump plugin.

OSBS can automatically bump the release number, for that
we just need to drop the label from the Dockerfile

See https://pagure.io/ContainerSIG/container-sig/issue/1

Signed-off-by: Clement Verna <cverna@tutanota.com>

Dockerfile

@@ -3,14 +3,12 @@ FROM registry.fedoraproject.org/fedora:rawhide
 ENV NAME="glusterfs" \
     DESC="GlusterFS on Fedora" \
     VERSION=0 \
-    RELEASE=1 \
     ARCH=x86_64 \
     REPO="$FGC" \
     container=docker
 
 LABEL name="$REPO/$NAME" \
       version="$VERSION" \
-      release="$RELEASE.$DISTTAG" \
       architecture="$ARCH" \
       vendor="Red Hat, Inc" \
       summary="$DESC" \