[qa] Add --ignore-pattern option to exclude files from QA checks #299

[aoutifrak]

• Introduced --ignore-pattern <file_pattern> option to allow users to exclude specific files or directories.
• Supports ignoring patterns like node_modules and env, which are unnecessary for QA checks.
• Ensured compatibility with existing QA check functionality.

This enhancement provides flexibility in excluding non-essential files

Fixes #299

Checklist

• [x] I have read the OpenWISP Contributing Guidelines.
• [x] I have manually tested the changes proposed in this pull request.
• [ ] I have written new test cases for new code and/or updated existing tests for changes to existing code.
• [ ] I have updated the documentation.

Reference to Existing Issue

Closes #.

Please open a new issue if there isn't an existing issue yet.

Description of Changes

Please describe these changes.

Screenshot

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[codesankalp]

Also, please remove trailing whitespaces from your changes.

[coveralls]

coverage: 95.981%. remained the same when pulling 813f0974b26582fa342f9611f549d70684f47f9a on aoutifrak:ignore-files-qa-check-299 into cfbd63e7c40b5c4717b32e40f6de72edad496127 on openwisp:master.