issue: #10617 Regex extractor ending or staring with special character

[azizullah2017]

Proposed changes:

• ... fixed and issue , Regex extractor does not work on entity value staring or ending with special character #10617

https://github.com/RasaHQ/rasa/issues/10617 Status (please check what you already did):

• [ ] added some tests for the functionality
• [ ] updated the documentation
• [ ] updated the changelog (please check changelog for instructions)
• [ ] reformat files using black (please check Readme for instructions)

[CLAassistant]

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[tttthomasssss]

Hey @azizullah2017 👋 - just to check, are you still working on the PR and/or do you need any help getting it done?

[azizullah2017]

@tttthomasssss yes, I am working on this. working on changes.

[stale[bot]]

This PR has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[m-vdb]

Hi there! Thanks for your contribution. As the PR has been stale for a while, I'm closing it. Please feel free to reopen an issue / PR if the problem still occurs on latest rasa versions.