[tests] fix race condition in SRP recovery reboot test

[jwhui]

Resolve a pre-existing race condition in dind_srp_tc_11.exp:

• After the DUT reboots, the SRP server port changes.
• The test was checking 'srp client host state' immediately and matching 'Registered' from the pre-reboot state, before the client actually detected the port change and re-registered.
• Added a loop to wait for the client's registered server port to match the new server port before checking the host state.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 33.75%. Comparing base (2b41187) to head (6a2f528).
⚠️ Report is 1544 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #3444       +/-   ##
===========================================
- Coverage   55.77%   33.75%   -22.02%     
===========================================
  Files          87      143       +56     
  Lines        6890    17246    +10356     
  Branches        0     1413     +1413     
===========================================
+ Hits         3843     5822     +1979     
- Misses       3047    11117     +8070     
- Partials        0      307      +307     

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[jwhui]

/gemini review

[gemini-code-assist]

Code Review

This pull request updates the integration test script 'tests/scripts/expect/dind_srp_tc_11.exp' to check if the variable 'port_after' is defined. If it exists, the script parses the port from hexadecimal to decimal, waits for the SRP client server to update to the new port, and verifies the update completes successfully before proceeding with the host state registration check. There are no review comments, so I have no feedback to provide.