EthClient.BlockByHash stopped working on 1.11.2

[tclemos]

System information

Geth version: 1.11.2

Expected behaviour

return ethereum.NotFound error

Actual behaviour

panic with nil reference

Steps to reproduce the behaviour

call ethclient.BlockByHash with a block hash that doesn't exist in the blockchain

This is the PR that introduced the error: #26723

I've added a comment to the PR explaining the problem.

[fjl]

Fixed in #26817