fix: better error message for missing local tag

Aiming to help the following scenario better:

coop-cloud/organising#444 (comment)

pkg/recipe/recipe.go

@@ -317,7 +317,7 @@ func EnsureVersion(recipeName, version string) error {
 	logrus.Debugf("read %s as tags for recipe %s", strings.Join(parsedTags, ", "), recipeName)
 
 	if tagRef.String() == "" {
-		return fmt.Errorf("no published release discovered for %s", recipeName)
+		return fmt.Errorf("the local copy of %s doesn't seem to have version %s available?", recipeName, version)
 	}
 
 	worktree, err := repo.Worktree()