chore(PULL_REQUEST_TEMPLATE.md): replace solves with fixes to ensure issue linking

[Naman-Priyadarshi]

Pull Request description

Replaces 'fixes' with 'solves' in PULL_REQUEST_TEMPLATE.md to ensure issue linking with pull request as per https://docs.github.com/en/issues/tracking-your-work-with-issues/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword

Fixes #217

How to test these changes

• ...

Pull Request checklists

This PR is a:

• [ ] bug-fix
• [ ] new feature
• [x] maintenance

About this PR:

• [ ] it includes tests.
• [ ] the tests are executed on CI.
• [ ] the tests generate log file(s) (path).
• [x] pre-commit hooks were executed locally.
• [ ] this PR requires a project documentation update.

Author's checklist:

• [x] I have reviewed the changes and it contains no misspelling.
• [x] The code is well commented, especially in the parts that contain more complexity.
• [x] New and old tests passed locally.

Additional information

Reviewer's checklist

Copy and paste this template for your review's note:

## Reviewer's Checklist

- [ ] I managed to reproduce the problem locally from the `main` branch
- [ ] I managed to test the new changes locally
- [ ] I confirm that the issues mentioned were fixed/resolved

[Naman-Priyadarshi]

Missed the change for the template before, "Fixed" now :)

[github-actions[bot]]

:tada: This PR is included in version 0.7.0 :tada:

The release is available on:

• 0.7.0
• GitHub release

Your semantic-release bot :package::rocket: