Update proxy_startup.py

[ponopono0322]

Auto check and change docker container

Description

Fixed an issue(#22162) where docker containers were not automatically updated from eng/common/testproxy/target_version.txt file.

This is the process of checking the container named ambitious_azsdk_test_proxy and then force-deleting it if the versions do not match. This only deletes the container, not the image.

All SDK Contribution checklist:

• The pull request does not introduce [breaking changes]
• CHANGELOG is updated for new features, bug fixes or other significant changes.
• I have read the contribution guidelines.

General Guidelines and Best Practices

• Title of the pull request is clear and informative.
• There are a small number of commits, each of which have an informative message. This means that previously merged commits do not appear in the history of the PR. For more information on cleaning up the commits in your PR, see this page.

Testing Guidelines

• Pull request includes test coverage for the included changes.

[ghost]

Thank you for your contribution ponopono0322! We will review the pull request and get back to you soon.

[ghost]

All CLA requirements met.

[ponopono0322]

This is a scenario for the current change.

1. Check eng/common/testproxy/target_version.txt is old. In this scenario past version is 1.0.0-dev.20220805.3
   

2. Check docker container same as 1.

3. Change 1 to latest version. In this scenario latest version is 1.0.0-dev.20220810.2
   

4. Check the image of the docker container if it has been changed well(1.0.0-dev.20220805.3 -> 1.0.0-dev.20220810.2).

Also, azsdkengsys.azurecr.io/engsys/test-proxy image works better performance on Silicon Mac. Consider using it.
In AMD mode, it took 02:12.

In ARM mode, it took 01:23.

[mccoyp]

Thank you again for opening a PR!

[mccoyp]

This is great -- thanks again!!

[ponopono0322]

@mccoyp Thank you. Have a nice day!