since symfony 5, Length with min option allows empty string

[dbu]

while hunting a symfony 4 deprecation notice (yeah, i know we need to update that system), i realized that the min length validation will always allow empty string since symfony 5.

for symfony 5, we could set allowEmptyString to false, but in symfony 6 that option has been completely removed. the correct way to do it is to additionally assert that it is not blank.

from my understanding of json schema, a min length > 0 implies that the string may not be blank.

[dbu]

i will adjust test expections and add a test if necessary, but first wanted to check if my thinking is correct and if this is the right way to do things.

[dbu]

i now use the correct ::class constant for NotBlank and have adjusted the tests and fixtures. locally the tests are now green.

[Korbeil]

Thanks for contributing @dbu !