Add pre-commit hook to check for secrets

[diondrapeck]

Description

New hook will check for secrets in the code before it's committed to help prevent secrets from being pushed to the remote repository. Checks for

• api_key
• api_endpoint
• subscription_id
• resource_group
• project_name

This check doesn't run for remote runs (e.g. PR checks) for now since there are existing mock instances of each of these patterns already in the repo that would be caught. Checking at commit time only on staged files should be sufficient to prevent new secrets from being added.

Checklist

• I have read the contribution guidelines
• I have coordinated with the docs team (mldocs@microsoft.com) if this PR deletes files or changes any file names or file extensions.
• This notebook or file is added to the CODEOWNERS file, pointing to the author or the author's team.