Add drupal/rel_to_abs

For daily emails, I want all links to be absolute URLs so they work when
embedded in the sent emails.

This module does this.

As there is no Drupal 11 compatible release, I've had to add the Lenient
Composer endpoint and add patch the rel_to_abs module to make it D11
compatible.

If everything works, I'll update the issue and mark it as RTBC.

https://www.drupal.org/project/rel_to_abs
https://www.drupal.org/docs/develop/using-composer/using-the-drupal-lenient-composer-plugin
https://github.com/cweagans/composer-patches
https://www.drupal.org/project/rel_to_abs/issues/3434164

config/sync/filter.format.basic_html.yml

@@ -4,6 +4,8 @@ status: true
 dependencies:
   module:
     - editor
+    - markdown_easy
+    - rel_to_abs
 _core:
   default_config_hash: mclCbTlJwWJORez4Y1eX2MqA0aGjSMAoJb3TaBABcK8
 name: 'Basic HTML'
@@ -34,7 +36,7 @@ filters:
     status: true
     weight: -10
     settings:
-      allowed_html: '<br> <p> <h2 id> <h3 id> <h4 id> <h5 id> <h6 id> <cite> <dl> <dt> <dd> <a hreflang href> <blockquote cite> <ul type> <ol start type> <strong> <em> <code> <li> <img src alt data-entity-uuid data-entity-type height width data-caption data-align>'
+      allowed_html: '<br> <p> <h2 id> <h3 id> <h4 id> <h5 id> <h6 id> <cite> <dl> <dt> <dd> <a hreflang href> <blockquote cite> <ul type> <ol type start> <strong> <em> <code> <li> <img src alt height width data-entity-uuid data-entity-type data-caption data-align>'
       filter_html_help: false
       filter_html_nofollow: false
   filter_html_image_secure:
@@ -49,3 +51,17 @@ filters:
     status: true
     weight: 15
     settings: {  }
+  markdown_easy:
+    id: markdown_easy
+    provider: markdown_easy
+    status: false
+    weight: 0
+    settings:
+      flavor: standard
+      tips: ''
+  rel_to_abs:
+    id: rel_to_abs
+    provider: rel_to_abs
+    status: true
+    weight: 0
+    settings: {  }