staging/{web,graphql}: Post-migration cleanup

In separated commits, this:

• drops the graphql.staging reverse proxy reference (since we now reach graphql through https://webapp.staging.swh.network/graphql)
• drops also the graphql redirection (for the same reason ^)
• decommissions the webapp role for webapp.staging (which will be shutdown)
• drops the graphql.staging dns record

octo-diff pergamon

*******************************************
- Resource_record[graphql-staging/CNAME]
*******************************************
*** End octocatalog-diff on pergamon.softwareheritage.org

octo-diff rp0

*** Running octocatalog-diff on host rp0.internal.staging.swh.network
I, [2023-10-20T12:42:52.606752 #4079108]  INFO -- : Catalogs compiled for rp0.internal.staging.swh.network
I, [2023-10-20T12:42:53.463026 #4079108]  INFO -- : Diffs computed for rp0.internal.staging.swh.network
diff origin/production/rp0.internal.staging.swh.network current/rp0.internal.staging.swh.network
*******************************************
- Concat::Fragment[/etc/varnish/includes.vcl:graphql]
*******************************************
- Concat::Fragment[/etc/varnish/includes.vcl:vhost_graphql.staging.swh.network]
*******************************************
- Concat::Fragment[graphql_staging cacert]
*******************************************
- Concat::Fragment[graphql_staging cert]
*******************************************
- Concat::Fragment[graphql_staging dhparams]
*******************************************
- Concat::Fragment[graphql_staging key]
*******************************************
- Concat::Fragment[hitch::domain graphql_staging]
*******************************************
- Concat[/etc/hitch/graphql_staging.pem]
*******************************************
- Concat_file[/etc/hitch/graphql_staging.pem]
*******************************************
- Concat_fragment[/etc/varnish/includes.vcl:graphql]
*******************************************
- Concat_fragment[/etc/varnish/includes.vcl:vhost_graphql.staging.swh.network]
*******************************************
- Concat_fragment[graphql_staging cacert]
*******************************************
- Concat_fragment[graphql_staging cert]
*******************************************
- Concat_fragment[graphql_staging dhparams]
*******************************************
- Concat_fragment[graphql_staging key]
*******************************************
- Concat_fragment[hitch::domain graphql_staging]
*******************************************
- File[/etc/ssl/certs/letsencrypt/graphql_staging/cert.pem]
*******************************************
- File[/etc/ssl/certs/letsencrypt/graphql_staging/chain.pem]
*******************************************
- File[/etc/ssl/certs/letsencrypt/graphql_staging/fullchain.pem]
*******************************************
- File[/etc/ssl/certs/letsencrypt/graphql_staging/privkey.pem]
*******************************************
- File[/etc/ssl/certs/letsencrypt/graphql_staging]
*******************************************
- File[/etc/varnish/includes/01_graphql.vcl]
*******************************************
- File[/etc/varnish/includes/50_vhost_graphql.staging.swh.network.vcl]
*******************************************
- Hitch::Domain[graphql_staging]
*******************************************
- Profile::Hitch::Ssl_cert[graphql_staging]
*******************************************
- Profile::Letsencrypt::Certificate[graphql_staging]
*******************************************
- Profile::Varnish::Vcl_include[graphql]
*******************************************
- Profile::Varnish::Vcl_include[vhost_graphql.staging.swh.network]
*******************************************
- Profile::Varnish::Vhost[graphql.staging.swh.network]
*******************************************
- Varnish::Vcl[/etc/varnish/includes/01_graphql.vcl]
*******************************************
- Varnish::Vcl[/etc/varnish/includes/50_vhost_graphql.staging.swh.network.vcl]
*******************************************
*** End octocatalog-diff on rp0.internal.staging.swh.network

[1] Related to !651 (merged)

Refs. swh/infra/sysadm-environment#5095 (closed)