bug #9328 [2.3][Form] Changed FormTypeCsrfExtension to use the form's name as default intention (bschussek)

This PR was merged into the 2.3 branch.

Discussion
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[2.3][Form] Changed FormTypeCsrfExtension to use the form's name as default intention

Equivalent of #9327, merged into 2.3.

Commits
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c4abe83 Merge branch 'fix-csrf-default-2.2' into fix-csrf-default-2.3
b07c618 [Form] Changed FormTypeCsrfExtension to use the form's name as default intention
[Intl] Improved FormTypeCsrfExtension to use the type class as default intention if the form name is empty