🚨 roles: setup_http_site_forward: Rename

Roles names should be lowercase with underscores only.
ansible-lint complained:

    % ansible-lint -t role-name
    WARNING  Listing 1 violation(s) that are fatal
    role-name: Role name setup-http-site-forward does not match ``^[a-z][a-z0-9_]*$`` pattern.
    roles/setup-http-site-forward:1

    Read documentation for instructions on how to ignore specific rule violations.

                 Rule Violation Summary
     count tag       profile rule associated tags
         1 role-name basic   deprecations, metadata

    Failed after min profile: 1 failure(s), 0 warning(s) on 135 files.

Fixes: 85c09ea2ae ("Add role for apache forward site")

host-tau.yml

@@ -191,7 +191,7 @@
 
     - name: Setup forwarding for Discord invite
       include_role:
-        name: setup-http-site-forward
+        name: setup_http_site_forward
       vars:
         site_name: "{{ discord_invite_domain }}"
         # forward_to: "https://discord.com/invite/8FcDvAf"