fix(l1): add engine_getBlobsV2 to capabilities.

[mpaulucci]

Motivation
Fixing lighthouse error complaining endpoint is not supported

Description

• Add endpoint to capabilities

[Copilot]

Pull Request Overview

This PR addresses a Lighthouse error by adding the engine_getBlobsV2 capability to the execution layer client's supported capabilities list. This ensures the client properly advertises support for the newer version of the blobs endpoint.

Key changes:

• Added engine_getBlobsV2 to the CAPABILITIES array

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[github-actions]

Lines of code report

Total lines added: 1
Total lines removed: 0
Total lines changed: 1

Detailed view

+--------------------------------------------+-------+------+
| File                                       | Lines | Diff |
+--------------------------------------------+-------+------+
| ethrex/crates/networking/rpc/engine/mod.rs | 54    | +1   |
+--------------------------------------------+-------+------+