minor #18047 [Form] Remove evasive getOrigin sentence (alamirault)

This PR was merged into the 5.4 branch.

Discussion
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[Form] Remove evasive `getOrigin` sentence

Remove evasive `getOrigin` sentence as suggested in #17670 (comment)

Close #17670

Commits
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0d2486d [Form] Remove evasive getOrigin sentence

Author: OskarStark

components/form.rst

@@ -749,7 +749,6 @@ method to access the list of errors. It returns a
     $errors = $form['firstName']->getErrors();
 
     // a FormErrorIterator instance in a flattened structure
-    // use getOrigin() to determine the form causing the error
     $errors = $form->getErrors(true);
 
     // a FormErrorIterator instance representing the form tree structure