fix test for doctype #9

Job	Run time
test (ubuntu-latest, stable)	3m 35s
test (ubuntu-latest, stable, --no-default-features)	4m 15s
test (ubuntu-latest, nightly)	4m 56s
test (ubuntu-latest, nightly, --no-default-features)	5m 2s
test (windows-latest, stable)	5m 34s
test (windows-latest, stable, --no-default-features)	5m 4s
test (windows-latest, nightly)	10m 2s
test (windows-latest, nightly, --no-default-features)	9m 51s
test (macos-latest, stable)	2m 58s
test (macos-latest, stable, --no-default-features)	2m 40s
test (macos-latest, nightly)	6m 7s
test (macos-latest, nightly, --no-default-features)	5m 41s
	1h 5m 45s

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