fix(state) handle empty request in read provider

[guillaume-sainthillier]

Q	A
Branch?	3.2
Tickets	#6404
License	MIT
Doc PR	N/A

Hello, this PR let ReadProvider handle nullable request because RequestParser::getQueryString($request) expects a request object to work.

We had this bug when using provider in CLI during async export of a GetCollection operation

[soyuka]

nice catch, wasn't expecting code to be used like this but I see no reason it wouldn't work :)

let me know if you have more issues, commit message is also missing : after the fix(state)

[guillaume-sainthillier]

nice catch, wasn't expecting code to be used like this but I see no reason it wouldn't work :)

let me know if you have more issues, commit message is also missing : after the fix(state)

Thank you for quick review!
Indeed we do serialize query filters before turning on async mode, so no request is present :-)