Do not allow version-illegal characters

trigger_copr

@@ -40,6 +40,7 @@ last_version() {
     git ls-remote --tag "$UrlBase" \
       | grep '/tags/' \
       | cut -d/ -f3 \
+      | grep -v '[^0-9a-z.]' \
       | sort -V \
       | tail -1 \
       | sed "s/^v//"