Refactor Build, Versioning into `azure-sdk-tools`

[scbedd]

This PR...

• [x] Refactors scripts present under eng/versioning to namespace ci_tools.versioning within the azure-sdk-tools package. All Integration points in CI are flipped over to consume entrypoints defined in the setup.py.
• [x] Refactors build_packages.py and build_package.py into single module ci_tools.build. This function create_package within this module is used wherever packages are built.
• [x] Moves anything related to setup.py parsing into ci_tools.parsing. More specific, allows users access to ParsedSetup which has a classmethod from_path that can be aimed at any setup.py. Instead of a crazy tuple that we can get lost in the sauce in, it's just strongly typed members of a class now.
• [x] Moves anything related to processing of requirements into ci_tools.functions.
• [x] Type and doc comment all the moved common functionality

This will be the most painful of the refactoring effort, but we will be able to make iterative fixes quite quickly once this one is in.

Due to the relative risk. I am delaying this merge until post-August-release-week. This is a significant improvement, but nothing that can't wait for a week.

Contributes to #23146

[check-enforcer[bot]]

This pull request is protected by Check Enforcer.

What is Check Enforcer?

Check Enforcer helps ensure all pull requests are covered by at least one check-run (typically an Azure Pipeline). When all check-runs associated with this pull request pass then Check Enforcer itself will pass.

Why am I getting this message?

You are getting this message because Check Enforcer did not detect any check-runs being associated with this pull request within five minutes. This may indicate that your pull request is not covered by any pipelines and so Check Enforcer is correctly blocking the pull request being merged.

What should I do now?

If the check-enforcer check-run is not passing and all other check-runs associated with this PR are passing (excluding license-cla) then you could try telling Check Enforcer to evaluate your pull request again. You can do this by adding a comment to this pull request as follows: /check-enforcer evaluate Typically evaulation only takes a few seconds. If you know that your pull request is not covered by a pipeline and this is expected you can override Check Enforcer using the following command: /check-enforcer override Note that using the override command triggers alerts so that follow-up investigations can occur (PRs still need to be approved as normal).

What if I am onboarding a new service?

Often, new services do not have validation pipelines associated with them, in order to bootstrap pipelines for a new service, you can issue the following command as a pull request comment: /azp run prepare-pipelines This will run a pipeline that analyzes the source tree and creates the pipelines necessary to build and validate your pull request. Once the pipeline has been created you can trigger the pipeline using the following comment: /azp run python - [service] - ci

[scbedd]

The failures present on python - core regression tests align with existing failures. Not treating as a blocker. Addressing final spellcheck errors and merging this PR.

[scbedd]

The single failure during release is due to a known issue with the SemVer powershell scripts, and is not related to the refactor. Overriding and merging.

[scbedd]

/check-enforcer override