Fix bug in chanOpenAck handler verification

[hu55a1n1]

Closes: cosmos/ibc-rs#64

Description

Note that in the spec, chanOpenAck calls the verifyChannelState with the counterpartyChannelIdentifier that it receives from the ChanOpenAck datagram.

function chanOpenAck(
  portIdentifier: Identifier,
  channelIdentifier: Identifier,
  counterpartyVersion: string,
  counterpartyChannelIdentifier: string,
  proofTry: CommitmentProof,
  proofHeight: Height) {
    // ...
    abortTransactionUnless(connection.verifyChannelState(
      proofHeight,
      proofTry,
      channel.counterpartyPortIdentifier,
      counterpartyChannelIdentifier,            // <------------------------- here
      expected
    ))
    channel.state = OPEN
    channel.version = counterpartyVersion
    channel.counterpartyChannelIdentifier = counterpartyChannelIdentifier
    provableStore.set(channelPath(portIdentifier, channelIdentifier), channel)
}

---

PR author checklist:

• Added changelog entry, using unclog.
• Added tests: integration (for Hermes) or unit/mock tests (for modules).
• Linked to GitHub issue.
• Updated code comments and documentation (e.g., docs/).

Reviewer checklist:

• Reviewed Files changed in the GitHub PR explorer.
• Manually tested (in case integration/unit/mock tests are absent).

[adizere]

Looks good Shoaib 💯 LGTM!