Add QA Tools / Linters #67

We want to add CI/CD tools to all PDS Interop PHP repositories that are dependencies for this repository.

This ticket serves as full list of all the steps that need to be taken.
For all repositories the steps are more or less the same:

• Create a .github/workflows directory
• Create a YAML workflow file to lint for PHP syntax errors
• Create a YAML workflow file to check for PHP version compatibility (PHP Compat)
• Create a YAML workflow file to check for style violations (PHP CodeSniffer)
• Create a YAML workflow file to do security checks
• Create a YAML workflow file to run PHPUnit tests (similar to tests.yml)

This means our worklist is:

• solid-nextcloud

  • Workflow to lint for PHP syntax errors
  • Workflow to check for PHP version compatibility
  • Workflow to check for style violations
  • Workflow to do security checks
  • Workflow to run PHPUnit tests see Workflow to run PHPUnit tests #81

• php-solid-auth

  • Workflow to lint for PHP syntax errors
  • Workflow to check for PHP version compatibility
  • Workflow to check for style violations
  • Workflow to do security checks
  • Workflow to run PHPUnit tests

• php-solid-crud

  • Workflow to lint for PHP syntax errors
  • Workflow to check for PHP version compatibility
  • Workflow to check for style violations
  • Workflow to do security checks
  • Workflow to run PHPUnit tests

• flysystem-nextcloud

  • Workflow to lint for PHP syntax errors
  • Workflow to check for PHP version compatibility
  • Workflow to check for style violations
  • Workflow to do security checks
  • Workflow to run PHPUnit tests

• flysystem-rdf

  • Workflow to lint for PHP syntax errors
  • Workflow to check for PHP version compatibility
  • Workflow to check for style violations
  • Workflow to do security checks
  • Workflow to run PHPUnit tests

If so desired, this list can be broken out into separate tickets in each repo.