chore(ui): remove unused template "shared/user/blocked_users" (go-gitea#7213)

This was found during PR go-gitea#7109.
It can be removed according to Gusted,
  see also: https://codeberg.org/forgejo/forgejo/pulls/7109#issuecomment-2942122

Signed-off-by: Ellen Emilia Anna Zscheile <[email protected]>
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/7213
Reviewed-by: 0ko <[email protected]>
Co-authored-by: Ellen Emilia Anna Zscheile <[email protected]>
Co-committed-by: Ellen Emilia Anna Zscheile <[email protected]>

Author: fogti