Remove loading status spinner for hand raise lead button

What does this MR do and why?

Remove loading status spinner for hand raise lead button

• not needed and doesn't provide any value.
• see discussion in: #460538 (comment 1894791302)

Changelog: removed EE: true

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

Before	After
Screen_Recording_2024-05-06_at_5.57.35_PM	Screen_Recording_2024-05-06_at_6.01.39_PM

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

1. Setup gdk to simulate SaaS - https://docs.gitlab.com/ee/development/ee_features.html#simulate-a-saas-instance and restart GDK
2. create a group
3. In the gitlab admin UI, edit the group to be on an ultimate trial
4. In rails console, change the trial, trial start and end date for the group

   Group.last.gitlab_subscription.update_columns(trial_starts_on: Date.today, trial_ends_on: 30.days.from_now, trial: true)

5. Go to group -> settings -> billing page and fill in form for 'Talk to an expert' and submit. Notice no spinner on the 'Talk to an expert'

Related to #460538 (closed)