Fix unit tests #13382

Job	Run time
Core Blocks (18.x)	21m 8s
Core Content (18.x)	3m 31s
Core Blocks (20.x)	20m 48s
Core Content (20.x)	3m 43s
Core Blocks - Listing (18.x)	10m 48s
Core Volto Slate (18.x)	18m 2s
Core Blocks - Listing (20.x)	10m 40s
Core Volto Slate (20.x)	17m 36s
Core Basic (18.x)	12m 57s
Core Basic - Plone 5 (18.x)	12m 52s
Core Basic (20.x)	12m 16s
Core Control Panels (18.x)	4m 12s
Coresandbox (18.x)	11m 14s
Core Control Panels (20.x)	4m 19s
Working Copy (18.x)	3m 57s
Multilingual (18.x)	3m 32s
Project Generator (18.x)	7m 6s
Multilingual in Seamless Mode (18.x)	3m 7s
Project Generator (20.x)	6m 40s
Seamless Mode (18.x)	12m 44s
	3h 21m 12s

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