Reposition and restyle integration reset button

What does this MR do and why?

Related to #349761 (closed)

Updates the "reset" button for the integration form to conform to Pajamas.

Screenshots or screen recordings

Before	After

How to set up and validate locally

To set up an integration:

1. Navigate to a GitLab group.
2. Select Settings > Integrations from the left sidebar.
3. Select an integration to set up (for example, Asana).
4. Complete the form details. Generally, you can use random data for this.
5. Click Save changes.
6. Observe. The reset button should now be visible in the correct location.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.