Update schemas for ASDF standard 1.6.0 #263

Job	Run time
Run asdf-astropy development tests	2m 29s
Run asdf-astropy development tests	2m 33s
Python 3.12 Schema validation tests	35s
Python 3.12 Schema validation tests	3m 22s
Python 3.11 Schema validation tests	30s
Python 3.11 Schema validation tests	2m 34s
Python 3.10 Schema validation tests	25s
Python 3.10 Schema validation tests	3m 36s
Python 3.9 Schema validation tests	21s
Python 3.9 Schema validation tests	4m 8s
Twine check	27s
Twine check	50s
Code style checks	37s
Code style checks	46s
macOS	34s
macOS	7m 31s
Windows	25s
Windows	4m 43s
	36m 26s

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