Download shepherd.js from cdn.jsdelivr.net

Issue: https://progress.opensuse.org/issues/153145

Also update dist/rpm/update-cache.sh because the lr command apparently
does not do anything anymore:

    % osc service lr tar
    WARNING: Command 'lr' is obsolete

assets/assetpack.def

@@ -149,7 +149,7 @@
 < https://cdnjs.cloudflare.com/ajax/libs/chosen/1.7.0/chosen.jquery.js
 < https://cdnjs.cloudflare.com/ajax/libs/jquery-ujs/1.2.1/rails.js
 < javascripts/disable_animations.js [mode==test]
-< https://shepherdjs.dev/dist/js/shepherd.js
+< https://cdn.jsdelivr.net/npm/[email protected]/dist/js/shepherd.js
 
 ! anser.js
 < javascripts/anser-import.js

dist/rpm/update-cache.sh

@@ -1,5 +1,8 @@
 #! /bin/sh
 
+# Note: this might not work correctly anymore because the 'lr' command
+# was obsoleted.
+
 set -e
 
 export LC_ALL='en_US.UTF-8'
@@ -9,7 +12,7 @@ rm -f _service\:*
 rm -f *.tar *.cpio
 osc service lr
 # special call for tar buildtime service
-osc service lr tar
+osc service run tar
 
 SD=$PWD
 cd openQA