Add `assertStateDescriptionContains`

[Darocs]

I think adding a assertStateDescriptionContains would not be unreasonable

[alex-tiurin]

Could you extend the description and provide some samples.

[Darocs]

For example, in compose I have a validation for OutlinedTextField, and when the validation works through, it sets isError to either true or false.
In the code, I would like to change the stateDescription depending on the isError received.
For example stateDescription = if (isError) "invalid" else "valid"
In the test, I find the text field via contentDescription and check its validity via assertStateDescriptionContains("valid") or assertStateDescriptionContains("invalid")

I'm new to Ultron, so I don't know if this is the right idea

[Darocs]

You can also see how I solved this Issue in my Validation_Etude repository at this path: app/src/androidTest/java/en/polescanner/validation_etude/ui/reusable/components/Assertions.kt