fix: remove leading and trailing - caracter

entrypoint.sh

@@ -3,6 +3,7 @@
 slug_ref() {
     echo "$1" \
          | tr "[:upper:]" "[:lower:]" \
+         | sed -r 's#refs/.*/##;s/[~\^]+//g;s/[^a-zA-Z0-9]+/-/g;s/^-+\|-+$//g;s/^-*//;s/-*$//' \
          | cut -c1-63
 }