Install from git URL & by name panels misplaced in the UI

Steps to reproduce:

1. Open or create any Project
2. Navigate to Window > Package Manager
3. Click on the + button in the top left
4. Choose either "Install package by name..." or "Install package from git URL"

Actual results: Modal for additional input is opened on top of the top Package Manager buttons, user has to click away in order to see these buttons again

Expected results: Modal for additional input is opened right below the top Package Manager buttons

Reproducible with versions: 2023.3.0b1, 6000.0.15f1

Not reproducible with versions: 2021.3.41f1, 2022.3.41f1, 2023.3.0a19

Tested on (OS): Windows 11