The E2E docker-compose stack has been modified to include code
coverage for all scripts that are kept in /project and are not
in the exclusion list.
The start command for `deployer` container has been replaced
with a `start-e2e-test.sh` script, which will execute E2E tests,
generate a Clover report and then return the exit code of E2E test
process to make sure that CI is aware of the test result.
Whole idea for collecting E2E coverage has been inspired by the
[this][1] article. All of scripts in `deployer` container will
now start with additional wrapper-like PHP code, which checks
if the `PHP_CCOV_START_FILE` variable is present. If not,
then nothing happens, but if the variable points to a PHP file,
then that file is being included.
The `docker-compose.yml` file has `PHP_CCOV_START_FILE` configured
to point to a file, which sets up code coverage, that starts counting
which instructions in `/project` directory have been called. Once
`php` interpreter starts shutting down, the coverage report is being
dumped into temporary files.
Once all tests have been processed, a script for merging partial
coverage reports is executed and finally a Clover code coverage file
is stored in the path defined in the `PHP_CCOV_OUTPUT_FILE` env var.
[1]: https://tarunlalwani.com/post/php-code-coverage-web-selenium/
As well rename test dir to tests, as Pest does not support dir without s on the end.
Also, remove PHP requirement from composer.json as we already have check-in bin/dep and it's better to have the check only in one place (now they already out of sync).
