Add information about running phpstan?

[sypets]

I don't know if this is really necessary, but I saw that bamboo runs it and it is pretty easily done to execute it locally, and make sure the code is ready for a higher level.

Currently level 2 is used, which is not very high.

./bin/phpstan analyse --no-progress --no-interaction

./bin/phpstan analyse --no-progress --no-interaction -l3

[sypets]

see also blog post about integrating phpstan in PhpStorm: https://susi.dev/phpstan-phpstorm-pro

[sypets]

Running phpstan is available via runTests.sh: runTests.sh -s phpstan.

This is also listed here: https://docs.typo3.org/m/typo3/guide-contributionworkflow/main/en-us/Testing/Index.html#commands

I am closing.