fix: use universal scope for fish_user_paths (#1699)

Co-authored-by: James Hegedus <[email protected]>

Author: bakotaco

asdf.fish

@@ -13,10 +13,10 @@ end
 # Do not use fish_add_path (added in Fish 3.2) because it
 # potentially changes the order of items in fish_user_paths
 if not contains $_asdf_bin $fish_user_paths
-    set --global --prepend fish_user_paths $_asdf_bin
+    set --universal --prepend fish_user_paths $_asdf_bin
 end
 if not contains $_asdf_shims $fish_user_paths
-    set --global --prepend fish_user_paths $_asdf_shims
+    set --universal --prepend fish_user_paths $_asdf_shims
 end
 set --erase _asdf_bin
 set --erase _asdf_shims