Fix the potentially inconsistent issue.

[arcane4096]

What type of PR is this?
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What does this PR do? Why is it needed?
If the endpoint parameter of the execution layer specifies a domain name, for example: --execution-endpoint=http://execution-domain:8551, and the execution layer clients corresponding to the domain name include Geth and Reth, then when Reth client is accessed first and the list of capabilities obtained contains engine_getBlobsV1. However, when the connection is reconnected to Geth client, engine_getBlobsV1 is not removed from capabilityCache, which may lead to unexpected results.

• Geth Engine API Capabilities(before version 1.14.12): https://github.com/ethereum/go-ethereum/blob/f3c696fa1db75d0f78ea47dd0975f6f0de6fdd84/eth/catalyst/api.go#L84
• Reth Engine API Capabilities(after version 1.0.6): https://github.com/paradigmxyz/reth/blob/890f082453490828258dbb9d84e131f55f65cb25/crates/rpc/rpc-engine-api/src/capabilities.rs#L4

Acknowledgements

• I have read CONTRIBUTING.md.
• I have made an appropriate entry to CHANGELOG.md.
• I have added a description to this PR with sufficient context for reviewers to understand this PR.

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[terencechain]

I think this makes sense. I wonder how it would work when a single beacon node is driving multiple execution layer clients:

• One Prysm instance drives both Geth and Reth. Geth supports get_blobs, but Reth does not
• Prysm connects to Geth first, then connects to Reth
• Prysm will not use get_blobs even though it could

[arcane4096]

Hi, From the code, it can be seen that after requesting engine_exchangeCapabilities and obtaining results, the save function is called, and the cache does not clear the previous old cache data.

If Reth returns [engine_getBlobsV1, OTHERS], but when requesting Geth, it returns [OTHERS], and since the cache is not cleared, calling cache.has("engine_getBlobsV1") again will return true, and the subsequent logic will be executed (which may not have a significant impact).

[arcane4096]

Hi @terencechain A more likely scenario is that Geth runs on a version 1.14.12 for a while and then reverts to a version below 1.14.12 .

Geth supports engine_getBlobsV1 starting from version 1.14.12