Add composer phpunit:coverage script

DEVELOPMENT.md

@@ -137,6 +137,15 @@ at least `phpdbg -qrr`(which has problems with switch case statements) as using
 php -d pcov.enabled=1 -d pcov.directory=. vendor/bin/phpunit --testsuite Unit --coverage-text
 ```
 
+If using the Docker-based development environment
+you can run the following script to retrieve a coverage report.
+```sh
+docker compose exec es_workspace composer phpunit:coverage
+```
+
+A browsable HTML version is available at http://localhost:5080/coverage/index.html .
+
+
 ### Var Dump server
 Symfony Var Dump server is configured to allow for easier debugging. It is not meant as a replacement for xdebug but can actually be used together with xdebug.
 This Var Dump Server is especially useful for when you want to debug a request without messing up the output e.g API calls ot HTML layout.

composer.json

@@ -23,7 +23,9 @@
             "composer phpcs:setup",
             "phpcbf -p"
         ],
-        "phpstan": "phpstan"
+        "phpstan": "phpstan",
+        "phpunit": "phpunit",
+        "phpunit:coverage": "phpunit --coverage-text --coverage-html ./public/coverage/"
     },
     "require": {
         "php": ">=8.1.0",