Merging develop into main

• Review home page and concept index page
• Fix link to library
• Update instructions on how to contribute to documentation
• Ensure destination directory for MR deployments exists
• Set "next steps" order to be the same as in lhs nav
• Remove gitlab CI file which is now defined in a protected space
• Feature/eca set field value

include/plugins/eca_content/action/eca_set_field_value/method.md

@@ -8,4 +8,4 @@ Available options:
 - **Prepend when not full yet**: If the field allows multiple values, the given value will be inserted as the first item, if the max. cardinality is not reached yet. Otherwise, this action will be skipped.
 - **Prepend and drop first when full**: Same as above, but if the max cardinality has been reached, the first value will be removed and the new value inserted at the beginning to the list.
 - **Prepend and drop last when full**: Same as above, but instead of dropping the first, this will drop the last item before inserting the new value at the beginning of the list.
-- **Remove value instead of adding it**: Remove the value from a multi-value field, if it's caontained in the list of existing items.
+- **Remove value instead of adding it**: Remove the value from a field, if it's contained in the list of existing items. If this removes the last remaining value of the field, then the field will be empty (for an example of this, see [this issue](https://www.drupal.org/project/eca/issues/3504388)).