test: add python-tuf v3.0.0 support #710

Job	Run time
tests / Collect available Go versions	5s
tests / golangci (1.18, ubuntu-latest)	12s
tests / golangci (1.18, macos-latest)	53s
tests / golangci (1.18, windows-latest)	50s
tests / golangci (1.19, ubuntu-latest)	32s
tests / golangci (1.19, macos-latest)	48s
tests / golangci (1.19, windows-latest)	2m 2s
tests / golangci (1.20, ubuntu-latest)	38s
tests / golangci (1.20, macos-latest)	46s
tests / golangci (1.20, windows-latest)	2m 18s
tests / run (ubuntu-latest, 1.18)	1m 54s
tests / run (ubuntu-latest, 1.19)	1m 12s
tests / run (ubuntu-latest, 1.20)	1m 16s
tests / run (macos-latest, 1.18)	1m 44s
tests / run (macos-latest, 1.19)	1m 22s
tests / run (macos-latest, 1.20)	1m 26s
tests / run (windows-latest, 1.18)	2m 30s
tests / run (windows-latest, 1.19)	5m 12s
tests / run (windows-latest, 1.20)	3m 37s
tuf	0s
tuf-client	0s
	29m 17s

Provide feedback