chain: Do not use the block cache for is_on_main_chain #11652

Job	Run time
Clippy linting	2m 8s
Check rustfmt style	25s
Build in release mode	1m 37s
Subgraph Runner integration tests	2m 57s
Run unit tests	3m 59s
Run integration tests	4m 31s
	15m 37s

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