FR: Disabling of My Account Page Access with New Config Setting

[bgarrant]

Description

It would be great to disable the My Account page in the production environment when 'allowAdminChanges' => false, is used. A separate setting like 'allowMyAccountChanges' => false, would be better as some people may want this enabled. With this setting and using the Solo version for a site, you can prevent the friend/client from changing the single email, password, photo, etc. which would in turn lock the administrator out of the CP.

Steps to reproduce

1. enable 'allowAdminChanges' => false in production environment in general.php
2. Make it so the My Account section can be disabled with new 'allowMyAccountChanges' => false setting

Additional info

• Craft version: Craft CMS 3.1.27
• PHP version: 7.1+
• Database driver & version: 5.7
• Plugins & versions: none