feat: add ssz support to builder api #20497

Job	Run time
Build	2m 23s
Build	2m 23s
Endpoint sim tests	3m 41s
Endpoint sim tests	3m 41s
Eth backup provider sim tests	7m 59s
Eth backup provider sim tests	7m 59s
Deneb sim tests	6m 14s
Deneb sim tests	6m 14s
Mixed clients sim tests	8m 10s
Mixed clients sim tests	8m 10s
Multifork sim test	12m 51s
Multifork sim test	12m 4s
	1h 21m 49s

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