Clarify origin of From address used in password reset emails (#6219)

CONTRIBUTORS.rst

@@ -470,6 +470,7 @@ Contributors
 * Jean Zombie
 * Pascal Widdershoven
 * Max Gabrielsson
+* Steven Wood
 
 Translators
 ===========

docs/reference/settings.rst

@@ -193,7 +193,7 @@ This specifies whether users are allowed to change their passwords (enabled by d
 
   WAGTAIL_PASSWORD_RESET_ENABLED = True
 
-This specifies whether users are allowed to reset their passwords. Defaults to the same as ``WAGTAIL_PASSWORD_MANAGEMENT_ENABLED``.
+This specifies whether users are allowed to reset their passwords. Defaults to the same as ``WAGTAIL_PASSWORD_MANAGEMENT_ENABLED``. Password reset emails will be sent from the address specified in Django's ``DEFAULT_FROM_EMAIL`` setting.
 
 .. code-block:: python
 
@@ -222,7 +222,7 @@ Email Notifications
 
   WAGTAILADMIN_NOTIFICATION_FROM_EMAIL = 'wagtail@myhost.io'
 
-Wagtail sends email notifications when content is submitted for moderation, and when the content is accepted or rejected. This setting lets you pick which email address these automatic notifications will come from. If omitted, Django will fall back to using the ``DEFAULT_FROM_EMAIL`` variable if set, and ``webmaster@localhost`` if not.
+Wagtail sends email notifications when content is submitted for moderation, and when the content is accepted or rejected. This setting lets you pick which email address these automatic notifications will come from. If omitted, Wagtail will fall back to using Django's ``DEFAULT_FROM_EMAIL`` setting if set, or ``webmaster@localhost`` if not.
 
 .. code-block:: python