Spring Fix SpEL propertyReadWriteWithRootObject() test

Partially modify PropertyAccessTests#propertyReadWriteWithRootObject. The test case is for method 'withRootObject' but actually it's copied for the previous case.

Comment From: sbrannen

Good catch. That test method is indeed not testing what it's intended to.

And congratulations on submitting your first PR to the Spring Framework! 👍

Comment From: sbrannen

This has been merged into 5.3.x and main.

Thanks

As a side note, your fix made me notice a similar issue in another test method in that class, which I fixed in 59c6b7e44543d3fdadfb78ae3c6a7c76de2fce91.