Personal Settings: Make API Token text field readonly
Summary:
In your personal settings, when displaying an API Token, that `AphrontFormTextControl` text field is editable. That is confusing as you cannot edit the token.
Thus allow to `setReadOnly()` on `AphrontFormTextControl` by copying the existing implementation from `AphrontFormTextAreaControl`, and use that in `PhabricatorConduitTokenEditController`.
Refs T16177
Closes T16178
Test Plan:
* Go to http://phorge.localhost/settings/panel/apitokens/
* Click "Generate Token"
* In the resulting text field displaying the token, try to edit the text
* Go back to overview at http://phorge.localhost/settings/panel/apitokens/, click on an existing token to open it
* In the resulting text field displaying the token, try to edit the text
Reviewers: O1 Blessed Committers, mainframe98, valerio.bozzolan
Reviewed By: O1 Blessed Committers, mainframe98, valerio.bozzolan
Subscribers: tobiaswiese, valerio.bozzolan, Matthew, Cigaryno
Maniphest Tasks: T16178, T16177
Differential Revision: https://we.phorge.it/D26195