Make code pass the gitlab pipeline

daniel.j → made their first commit to this issue’s fork.

Added a .gitlab-ci.yml file and implemented phpstan, phpcs and cspell fixes.

Gitlab CI pipeline passing (https://git.drupalcode.org/issue/mollie_donations-3458108/-/pipelines/32...).

Please review, thanks.

Added minor suggestions to MR, please check ~~ moving back into NW.

Working on the suggestions.

Great~~ let me know once you are done

@ankitv18, Done with the changes.
Kindly check

Looks good ~~ Hence marking RTBC.