[Python] python regex validation generation (!11525) · Merge requests · OpenAPI Tools / openapi-generator

Created by: aaronatbissell

This removes some code that was not correctly generating regex validation patterns. It's basically a revert of #10920 and fixes #11521 (closed).

Technical team: @taxpon @frol @mbohlool @cbornet @kenjones-cisco @tomplus @Jyhess @arun-nalla @spacether

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Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
Run the following to build the project and update samples:
```
./mvnw clean package 
./bin/generate-samples.sh
./bin/utils/export_docs_generators.sh
```
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