Fleet UI: Dropdown styling nits (centering/padding)

[RachelElysia]

Fleet version: <!-- Copy this from the "My account" page in the Fleet UI, or run fleetctl --version --> main Web browser and operating system:

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💥  Actual behavior

The main dropdown for Hosts, Software, and Queries table have the following issues:

• The dropdown text is not vertically centered, looks like the container is 2px shy of the entire height
• The dropdown options feel like they're cut off at the bottom

🧑‍💻  Steps to reproduce

1. Look at table dropdowns

Video of nits

https://www.loom.com/share/6fdcd1ccf84a419e9bdbe1c4be68839b?sid=adc6b92f-4015-4011-8c18-ddb04fdba1e9

🕯️ More info (optional)

N/A

FE

[RachelElysia]

Another instance of cutting off needs fixing: