Add ability to pick Jira PATs with bearer token auth, instead of basic auth to enable connecting Jira Data Center edition

Description

API token for Jira in Atlassian cloud uses the Basic Auth method, which is not supported in Jira Data Center edition

When using the method of Jira Server user & password, Jira treats user&password based logins from Gitlab the same way as log-ins via the web interface.

For example, if the login fails for some reason (such as due to a random network issue), this will trigger a CAPTCHA on the Jira side.

Once CAPTCHA is activated for the server user gitlab, Gitlab-Jira integration won't be able to log in until a human notices this and solves the problem either by:

• logging into Jira as an administrator and clearing the failed logins to counter for the service account
• logging into Jira as the service account and solving the CAPTCHA

Since Gitlab-Jira integration doesn't report login issues, this can only be noticed later when Jira issues are not updated automatically by Gitlab commits.

Unfortunately, Jira doesn't allow disabling CAPTCHA for one particular account. For obvious reasons, disabling it for the entire Jira instance isn't desirable.

Proposal

For these reasons, using Personal Access Tokens is the best solution as they're not subject to the same checks (CAPTCHA) in Jira.

However, PATs with bearer tokens are needed.