fix: test environments inherit and modify local genesis.json

[s8sato]

Context

#5027 made test environments generate genesis.json by themselves, which took away the means to reflect local genesis.json changes to the test environments

Solution

Partially revert #5027 for docker compose and test_env.py to inherit and modify local genesis.json

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Review notes

• executor wasm_dir paths are resolved at the modified genesis.json. They aren't affected by the second resolution in RawGenesisTransaction::from_path during kagami genesis sign

Checklist

• I've read CONTRIBUTING.md.
• All review comments have been resolved.
• All CI checks pass.

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