Tests

refactor: converting some DocumentJoiner methods to staticmethod #15320

Job	Run time
format	14s
check-imports	16s
Unit / ubuntu-latest	2m 0s
Unit / windows-latest	5m 31s
Unit / macos-latest	1m 52s
Integration / windows-latest	6m 55s
Integration / macos-latest	6m 11s
Integration / ubuntu-latest	3m 36s
lint	1m 49s
Tests completed / Mark tests as completed	1s
	28m 25s

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