Turn on masking of new access token and remove reliance on `created-access-token` class

Part of https://gitlab.com/gitlab-org/gitlab/-/issues/357848.

Aim

• Set the masking on for new tokens (as default) and modify the QA end-to-end test to toggle the visibility of the new tokens.

• In addition, we want to rely on the new selector data-qa-selector="created_access_token_field" instead of the older created-access-token-field class. Accomplished by Update/remove old vue qa selectors (!94401 - merged)

Background

In !84373 (merged), we were unable to turn on the masking of new access token without modifying the QA end-to-end tests. Hence, we decided to initially show the token unmasked and later, on a follow up MR, turn the masking on.