git: introduce get_last_tag func

share/eterbuild/functions/git

@@ -100,11 +100,16 @@ git_commit_ignore_nothing()
         return 1
 }
 
+get_last_tag()
+{
+        git describe --abbrev=0 --tags
+}
+
 # check if tag is last commit tag (put on the last commit). if tag is missed, check with the last tag in repo
 is_last_commit_tag()
 {
         local TAG=$1
-        test -n "$TAG" || TAG=$(git describe --abbrev=0 --tags)
+        test -n "$TAG" || TAG=$(get_last_tag)
         # check if the tag put on the last commit
         [ "$(git rev-parse HEAD)" = "$(git rev-parse $TAG^0)" ]
 }