Docs: mention support emails (#12518)

Closes #12485

Author: stsewd

docs/user/support.rst

@@ -27,11 +27,15 @@ These provide step-by-step solutions to common user requests.
         Our team responds to support requests within 2 business days or earlier for most plans.
         Faster support response times and support SLAs are available with plan upgrades.
 
+        If you are unable to create or access your account, you can email us at [email protected].
+
    .. tab:: |org_brand|
 
         Please fill out the form at https://app.readthedocs.org/support/,
         and we will reply as soon as possible.
 
+        If you are unable to create or access your account, you can email us at [email protected].
+
 External resources
 ------------------