Cache always returns the first component variant that was requested by in the headless way

Steps to reproduce

1.  Create page with two component variants, assign cookie trait to the first variant, header trait to the second variant
2.  Request a page with component variant + cookie trait via rest delivery endpoint
3.  Make a request again, with a header trait

Expected results

Second (header) variant is returned.

Actual results

First (cookie) variant is returned.

Workaround

Disable cache.