Help box UI not matching updated U6.5 design: misaligned "Read more" link and oversized "Install sysroot and toolchain package" button

Steps to reproduce:

1. Create a Unity project
2. Install the "Linux" module if it was not installed (use the Hub for this)
3. Go to "Edit -> Project Settings"
4. Select the "Toolchain Management (Standalone Linux)", which should be displayed below the "Timeline"
5. Observe the help box displayed in the "Toolchain Management (Standalone Linux)" details window

Actual results: 

• The "Read more" link is displayed on the left side of the help box

• The "Install sysroot and toolchain package" button appears oversized and is positioned incorrectly within the layout

Expected results: Link and button should be displayed at the right size of the help box

Reproducible with versions: 6000.5.0a7

Not reproducible with versions: 6000.4.0b8

Tested on (OS): macOS - Tahoe 26.3