Added coverage commands for Herd users

[marcusmoore]

Description

This PR adds composer commands so Herd users can easily generate code coverage reports in clover or html format:

coverage:herd:clover
coverage:herd:html

Here is what they are aliases for:

herd coverage vendor/bin/phpunit --coverage-clover tests/coverage/clover.xml
herd coverage vendor/bin/phpunit --coverage-html tests/coverage/html

The reports are dumped to the tests/coverage/ directory after generating.

The html format is human-readable and the clover format can be imported to PHPStorm (and other IDEs) for direct referencing in the IDE.

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This is really just so I don't have to remember the longer commands that are aliased and I won't be mad if this isn't accepted (I can throw them into my bash aliases)...

Type of change

• Chore

[what-the-diff]

PR Summary

• Update to .gitignore File
  A new entry has been added to the .gitignore file. This means that certain test results will now be ignored by the Git version control system, specifically files under the tests/coverage/ directory. This helps keep our repository clean and free from clutter that doesn't necessarily need to be tracked.

• New Scripts Added to composer.json File
  Two new scripts coverage:herd:clover and coverage:herd:html have been added to the composer.json file. These scripts will provide new ways for us to check our code coverage. In other words, these tools will help us measure how much of our code is being tested, which is crucial in maintaining high code quality and identifying untested parts of our codebase.

[snipe]

Love it!