Update for ASDF standard 1.6.0 #869

Job	Run time
setup	5s
wheel_building / Build source and wheel distribution	5m 44s
asdf-schemas / Load tox environments	4s
core / Load tox environments	4s
asdf-schemas / asdf (ubuntu-latest)	2m 9s
asdf-schemas / asdf-standard (ubuntu-latest)	46s
asdf-schemas / asdf-transform-schemas (ubuntu-latest)	1m 50s
asdf-schemas / asdf-coordinates-schemas (ubuntu-latest)	3m 28s
core / py39-parallel-cov (ubuntu-latest)	2m 16s
core / py311-test-devdeps-parallel-cov (ubuntu-latest)	2m 49s
core / py39-astropylts-parallel-cov (ubuntu-latest)	2m 23s
core / py39-transformlts-parallel-cov (ubuntu-latest)	2m 13s
dev	0s
test	0s
oldest	0s
numpy	0s
	23m 51s

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