What does this PR do?

This PR fixes the issue of the time zone dropdown menu in the application extending beyond it's intended surface area when opened, causing it to overlap and obscure surrounding UI elements.

• Fixes #19398

Image Demo (if applicable):

Before:

After:

Desktop view -

Mobile view -

Mandatory Tasks (DO NOT REMOVE)

• I have self-reviewed the code (A decent size PR without self-review might be rejected).
• I have updated the developer docs in /docs if this PR makes changes that would require a documentation change. If N/A, write N/A here and check the checkbox.
• I confirm automated tests are in place that prove my fix is effective or that my feature works.

How should this be tested?

1. Go to /getting-started.
2. Click on the timezone dropdown.
3. Ensure it no longer overflows the intended area.
4. Resize the screen and test responsiveness

• Are there environment variables that should be set?
• What are the minimal test data to have?
• What is expected (happy path) to have (input and output)?
• Any other important info that could help to test that PR

Checklist

<!-- Remove bullet points below that don't apply to you -->

• I haven't read the contributing guide
• My code doesn't follow the style guidelines of this project
• I haven't commented my code, particularly in hard-to-understand areas
• I haven't checked if my changes generate no new warnings