Add utility function to call verifyBlobV2

[litt3]

Why are these changes needed?

• Recent discussions have yielded consensus that the eigenDA cert which gets published to rollup inboxes should contain the NonSignerStakesAndSignature, rather than the SignedBatch
• This PR introduces a verification utility to call VerifyBlobV2, which accepts the NonSignerStakesAndSignature
• It's possible that the VerifyBlobV2FromSignedBatch verification utility will be deleted at some point, but I think it makes sense to keep for now, until the v2 client implementation has solidified.

Checks

• I've made sure the tests are passing. Note that there might be a few flaky tests, in that case, please comment that they are not relevant.
• I've checked the new test coverage and the coverage percentage didn't drop.
• Testing Strategy
  • Unit tests
  • Integration tests
  • This PR is not tested :(