If the admin has not set the correct settings, the user should not see the connect button. That will avoid potential issues

* [ ] write unit tests for anything that can go wrong in `oauthRedirect`
* [ ] write unit tests for anything that can go wrong in `getOpenProjectOauthURL`
* [ ] refactor `getOpenProjectOauthURL`so that it throws an exception if any needed value is not set
* [ ] write tests for `\OCA\OpenProject\Settings\Personal::getForm`
* [ ] add check to `\OCA\OpenProject\Settings\Personal::getForm`for the case that `_getOpenProjectOauthURL_`_throws an error_
* [ ] add check to `\OCA\OpenProject\Settings\Personal::getForm`for the Begin of the insertioncase,End of the insertion Begin of the deletion caseEnd of the deletion that secret is not set (if we keep the secret in <mention class="mention" data-id="41128" data-type="work_package" data-text="#41128">#41128</mention> )
* [ ] don&#39;t show connect button in Begin of the insertionfiles tab, dashboard,End of the insertion Begin of the deletion filestab, dashboardEnd of the deletion or personal settings page if any required admin settings are not set Begin of the insertion(@kiranparajuli)End of the insertion