fix variable in autobuilder

debian/rules

@@ -79,13 +79,14 @@ binary: binary-indep binary-arch
 jenkins-build-official:
 	git-buildpackage --git-upstream-branch=origin/upstream --git-debian-branch=origin/debian --git-ignore-branch -kjenkins@ci.aegirproject.org
 
+version=`git describe --match 'debian/*' --tags | sed 's#debian/##;s/-\([0-9]*\)-\([0-9]*\)-/-\1+\2/'`
+
 # this builds a debian package but first updates the branches to follow the latest 1.x branch
 jenkins-build-auto:
 	git checkout -b upstream || git checkout upstream
 	git merge 6.x-1.x
 	git checkout -b debian || git checkout debian
 	git merge upstream
-	version=`git describe --match 'debian/*' --tags | sed 's#debian/##;s/-\([0-9]*\)-\([0-9]*\)-/-\1+\2/'`
-	dch -v $version "automatic jenkins build"
+	dch -v ${version} "automatic jenkins build"
 	git commit -m"dummy commit for $version autobuild" debian/changelog
 	git-buildpackage -kjenkins@ci.aegirproject.org