Add auto-release

[mtrezza]

New Feature / Enhancement Checklist

• I am not disclosing a vulnerability.
• I am not just asking a question.
• I have searched through existing issues.

Current Limitation

This repo has no release automation. Publishing a release takes more effort than it should.

Feature / Enhancement Description

Since packagist registry scans the repo automatically and published new releases there, release automation here only needs to incorporate the following tasks:

• Create changelog entry
• Bump SDK version in ParseClient.php (maybe via a simple sed instruction)
• Create version tag

[parse-github-assistant]

Thanks for opening this issue!

• 🎉 We are excited about your ideas for improvement!

[mtrezza]

Keeping this open until we can see with a PR merge that it actually works

[mtrezza]

It seems that the sed command has a slightly different syntax on ubuntu.

https://github.com/parse-community/parse-php-sdk/actions/runs/4839263132/jobs/8624178724

[parseplatformorg]

🎉 This change has been released in version 2.1.0