Function expectElementToHaveClassContaining

expectElementToHaveClassContaining(
    page: any,
    selectorKey: string,
    classKey: string,
): Promise<void>
Gets an element by selector and asserts it has a class containing the specified text.
Parameters
- page: any
- selectorKey: string
- classKey: string
Returns Promise<void>
Example
```
Then I pw get element by selector "button.primary" to have class containing "active"
```
- Defined in backend/assertions/elements.ts:308