Need some works on making tests look more friendly

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Is your feature request related to a problem? Please describe:

Ref to question: #2705. Use this issue to track the progress.

Describe the feature you'd like:

works need to do:

add more description/guide/schematic diagram for running integration test on github workflow and local, like the detail step, or the recommend way, or things we should pay attention to.
need a script to download dependent binary for local integration test, can ref to the ci : https://github.com/PingCAP-QE/ci/blob/0168669f271712bcde92dff2603fcf962d90c69b/jenkins/pipelines/ci/ticdc/integration_test_common.groovy#L242-L279 (https://github.com/pingcap/ticdc/pull/3502)
reduce debug outputs of every integration test, redirect to other medias. Output sketch info just like gtest or testify.
need an overview for current integration tests，make category and workflow description.
need a brief introduction for workflow of integration test on github for new contirbutor

Describe alternatives you've considered:

Teachability, Documentation, Adoption, Migration Strategy:

Research direction: Review the existing integration test documentation and scripts in the repository, and identify gaps and improvements as listed in the checkboxes. Focus on creating a guide for running integration tests locally and on GitHub Actions, and propose a script to download dependencies. Note the example CI script linked in the issue.
Tech stack: go
Domain: backendtesting
Issue type: Documentation
Difficulty: 2
Estimated time: Half day
Activity status: Fresh
Clarity: Clear
Prerequisites: GitGo
Newbie friendliness: 80