Views Exposed Form Fieldset doesn't respect simple fielset element

Please review and test

Changes were tested and looks good to me.
We are going to use it as a patch for now in our project, but would be great if it can be merged and released in next module versions.

Apologies, MR now conflicts.

I reworked the patch to fix the conflict.

@viniciusrp can you please update the merge request instead of posting patches? That will run the CI.

Conflicts in MR were fixed