Adding codecov support (or trying to, anyway)

[snipe]

Attempting to add Codecov integration - we've tried this before and it didn't work so well, but that was a while ago.

[what-the-diff]

PR Summary

• Introduces a New Workflow File
  A new workflow file (".github/workflows/ci.yml") gets added, designed to streamline the interaction with a tool called 'Codecov', a service that helps measure the impact of your code changes.

• Workflow Triggers
  The new process is automatically triggered during any 'push' or 'pull request' event, ensuring code changes are validated in real-time.

• Workflow Environment
  The workflow operates in the latest Ubuntu environment, a reliable and popular operating system, to guarantee performance and compatibility.

• Primary Workflow Steps
  This workflow performs a series of tasks, including code checkout, setting up a latest PHP version (8.2), managing dependencies, running tests, collecting test coverage data, and then uploading it to 'Codecov'.

• Workflow Action Tools
  To accomplish these tasks, the workflow employs different components: 'actions/checkout@v2' is used to extract the code, 'shivammathur/setup-php@v2' helps in setting up PHP, while 'codecov/codecov-action@v3' handles the coverage report uploading.

• Code Conciseness
  Despite its complexity, the workflow was compactly written, merely consuming 18 lines of code, which enhances readability and maintenance.