test: handle missing peer addrbind

[thepastaclaw]

Fixes the unresolved CodeRabbit finding forwarded from dashpay#7124.

getpeerinfo documents addrbind as optional, so use peer.get("addrbind") while preserving the existing exact (addr, addrbind) match and uniqueness assertion.

Validation:

• python3 -m py_compile test/functional/test_framework/test_node.py
• git diff --check
• separate local backport prerequisite gate at ffe93588fe819e2fddf7d2f26598d6d54aee3ba3: PASS, zero findings

Original thread: dashpay#7124 (comment)

[github-actions]

✅ No Merge Conflicts Detected

This PR currently has no conflicts with other open PRs.

[thepastaclaw]

The linux64_tsan-test failure is unrelated to this PR and matches the known p2p_blocksonly.py TSAN flake tracked in dashpay#7436.

All three attempts timed out at second_peer.wait_for_tx(txid) after 240 seconds, with no ThreadSanitizer report. This PR only changes the TestNode peer metadata lookup from peer["addrbind"] to peer.get("addrbind"); behavior is unchanged when addrbind is present, and the change does not affect transaction relay. The same test passed locally on current upstream/develop.

The PR is proper as-is. No branch change, history rewrite, empty commit, push, or CI retrigger is needed for this unrelated failure.

[thepastaclaw]

@vijaydasmp This remains blocked only by the July 10 linux64_tsan-test timeout in p2p_blocksonly.py (the known dashpay#7436 flake); every other job passes and head ffe93588 is still mergeable. I cannot rerun this repository’s Actions job with the current token. Could you rerun the failed job or make the final merge/close decision? No branch change is indicated by this failure.

[thepastaclaw]

@vijaydasmp Nine-day follow-up: head ffe93588 is still mergeable and every check except the known p2p_blocksonly.py TSAN timeout passes. That failure remains tracked as dashpay#7436 and does not indicate a branch change. Could you rerun the failed job or make the final merge/close decision?