fix: remove deprecated cy.state('subject')

[warpdesign]

What:

Replace cy.state('subject') by cy.currentSubject().

Why:

cy.state('subject') is being deprecated:

How:

Replace cy.state('subject') by cy.currentSubject() in utils.ts.

Checklist:

• [ ] Documentation N/A
• [x] Tests
• [x] Ready to be merged

[skvale]

Linking the PR that deprecated this: https://github.com/cypress-io/cypress/pull/23092

While we would normally consider internal state to be internal, cypress-testing-library relies on cy.state('subject'). Therefore, this PR includes a shim to keep that call working as before. Once this PR is released, we will follow up with them to move over to the new call, ensuring that no end users (with or without cypress-testing-library) ever experience disruption (beyond the console warning).

[TylorMayfield]

My console appreciates it

[marctorrelles]

Hi! Do you think we can get this merged? Thanks 😄

[olaj]

It would be awesome if this gets merged, if it works that is.

[NicholasBoll]

Duplicate of #233