feat(CI/CD): add dependabot for automatic dependency updates

[harmeetsingh11]

Related Issue:

Fixes #250

Description:

This Pull Request addresses the need to automate the management of project dependencies for enhanced stability, security, and maintenance.

Changes Proposed:

1. Dependabot Integration: Add Dependabot to the project.
2. Automated Dependency Updates: Upon activation, Dependabot will automatically submit pull requests (PRs) when outdated dependencies are identified in our client/package.json and server/package.json files.

Benefits:

• Stability: Ensures the project remains stable by adopting the latest versions of dependencies.
• Security: Enhances security by promptly addressing and updating vulnerable dependencies.
• Maintenance: Automates the process, reducing manual effort and ensuring continuous improvement.

Checklist:

• [X] Dependabot integrated successfully.

@hereisSwapnil please review this PR. After merging the PR, please don't forget to add gssoc, level labels and assign me the PR. Otherwise my points won't be added. Thanks