To be integrated as part of MDL-81266
When running PHPUnit 9.6 we get the following deprecation warnings:
"assertObjectHasAttribute() is deprecated and will be removed in PHPUnit
10. Refactor your test to use assertObjectHasProperty() instead."
So we replace all instances of assertObjectHasAttribute with
assertObjectHasProperty.
PHPUnit justifies the change with:
> PHPUnit currently refers to "fields" (see above) as "attributes". This
> is (or will become) confusing considering the introduction of
> attributes in PHP 8 and their support in PHPUnit. PHPUnit will be
> changed to use the term "property" instead of "attribute" where "field"
> is meant.
Signed-off-by: Daniel Ziegenberg <daniel@ziegenberg.at>