footprint properties dialog: small improvements

Description

The footprint properties dialog (in pcbnew) got some changes in the last weeks. The changes in the bottom part of this dialog could need some refinement (compared with older v7 version).

• reduce new UUID-string to same small font as library-link
• try to move OK+Cancel button some mm up

Steps to reproduce

1. open kicad v7 + v7.99 in parallel, load any project (in both), open board (in both)
2. doubleclick any footprint --> get footprint properties dialog --> compare bottom part of dialog for both versions
3. notice: v7.99 needs much more (wasted) space

KiCad Version

Application: KiCad PCB Editor x64 on x64

Version: 7.99.0-1776-ge53e571d2d, release build

Libraries:
	wxWidgets 3.2.2
	FreeType 2.12.1
	HarfBuzz 6.0.0
	FontConfig 2.14.1

Platform: Windows 10 (build 19045), 64-bit edition, 64 bit, Little endian, wxMSW

	wxWidgets: 3.2.2 (wchar_t,wx containers)
	Boost: 1.81.0
	OCC: 7.7.1
	Curl: 7.88.1-DEV
	ngspice: 40
	Compiler: Visual C++ 1936 without C++ ABI

Build settings: