Issues/52 python dependencies to requirements

[shwetd19]

Checklist

• I have read the [OpenWISP Contributing Guidelines](http://openwisp.io/docs/developer/contributing.html).
• I have tested the changes in this pull request to make sure they work.
• I have added or updated tests for any new or changed code.
• I have updated the documentation where needed.

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Reference to Existing Issue

Closes #52.

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Description of Changes

This pull request moves Python dependencies from pip.yml to a requirements.txt file for easier management. Here’s what was done:

1. Created a requirements.txt file:

   • Added all dependencies, such as Flask, Werkzeug, and uwsgi, into this file to keep things organized.

2. Updated pip.yml:

   • Adjusted the Ansible tasks to install dependencies from requirements.txt instead of listing them directly in the file.
   • Added steps to:
     • Update pip and related tools like setuptools and wheel.
     • Install dependencies in a virtual environment using the requirements.txt file.

3. Dependabot Integration:

   • Made sure tools like Dependabot can track and update dependencies in requirements.txt automatically.

4. Tested the Changes:

   • Ran the updated playbook to confirm everything works as expected.

These changes make it easier to manage and update dependencies while keeping the setup clean and consistent.

[pandafy]

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