[Tiers] Misaligned options

[Nylilsa]

Describe the bug Some options may appear slightly more above than others are.

To Reproduce Steps to reproduce the behavior:

1. In the textfield of Add tier, enter <p
2. Click on the button Add tier. The tier that appears should be empty.
3. Select the created tier. The textfield should say <p.
4. Replace the text <p by <p>.
5. Press Save Changes

Edit: Alternatively, there is an easier way to reproduce it.

1. In the textfield of Add tier, enter hello
2. Click on the button Add tier.
3. Select the created tier.
4. Replace the text hello by (nothing).
5. Press Save Changes

[MaribelHearn]

Fixed as of https://github.com/MaribelHearn/maribelhearn.com/commit/52410680aeecc3e0b940fc6203184d8c2f55f531