Add schema checker to `json` module #8419

Job	Run time
Ruby analysis (ubuntu-latest, nightly-latest)	41s
Ruby analysis (ubuntu-latest, default)	36s
Ruby analysis (macos-latest, default)	1m 2s
Ruby analysis (macos-latest, nightly-latest)	1m 0s
Ruby analysis (ubuntu-latest, linked)	42s
Ruby analysis (macos-latest, linked)	50s
	4m 51s

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