Fix for AgentIpInIpTunnelTest.DecapPacketParsing

[itskittycisco]

Pre-submission checklist

• I've ran the linters locally and fixed lint errors related to the files I modified in this PR. You can install the linters by running pip install -r requirements-dev.txt && pre-commit install
• pre-commit run
  clang-format.............................................................Passed
  black................................................(no files to check)Skipped
  shellcheck...........................................(no files to check)Skipped
  shfmt................................................(no files to check)Skipped
  trim trailing whitespace.................................................Passed
  fix end of files.........................................................Passed
  check yaml...........................................(no files to check)Skipped
  check json...........................................(no files to check)Skipped
  check for merge conflicts................................................Passed
  ruff check...........................................(no files to check)Skipped

Summary

Test Plan

Manually executed AgentIpInIpTunnelTest.DecapPacketParsing

[Tianyu-Meta]

Close this PR as >= 25.5 we use the PIPE mode and keep the code unchanged so 24.8 (using uniform mode) will still pass