Use stricter regex in bridges' registration.yaml

I've been thinking of doing before, but haven't.

Now that the Whatsapp bridge does it (since 4797469383),
it makes sense to do it for all other bridges as well.
(Except for the IRC bridge - that one manages most of registration.yaml by itself)

roles/matrix-bridge-mautrix-facebook/defaults/main.yml

@@ -171,7 +171,7 @@ matrix_mautrix_facebook_registration_yaml: |
   namespaces:
     users:
     - exclusive: true
-      regex: '@facebook_.+:{{ matrix_mautrix_facebook_homeserver_domain|regex_escape }}'
+      regex: '^@facebook_.+:{{ matrix_mautrix_facebook_homeserver_domain|regex_escape }}$'
   url: {{ matrix_mautrix_facebook_appservice_address }}
   sender_localpart: facebookbot
   rate_limited: false

roles/matrix-bridge-mautrix-telegram/defaults/main.yml

@@ -367,10 +367,10 @@ matrix_mautrix_telegram_registration_yaml: |
   namespaces:
       users:
       - exclusive: true
-        regex: '@telegram_.+:{{ matrix_mautrix_telegram_homeserver_domain|regex_escape }}'
+        regex: '^@telegram_.+:{{ matrix_mautrix_telegram_homeserver_domain|regex_escape }}$'
       aliases:
       - exclusive: true
-        regex: '#telegram_.+:{{ matrix_mautrix_telegram_homeserver_domain|regex_escape }}'
+        regex: '^#telegram_.+:{{ matrix_mautrix_telegram_homeserver_domain|regex_escape }}$'
   url: {{ matrix_mautrix_telegram_appservice_address }}
   sender_localpart: telegrambot
   rate_limited: false