[VRF-887] Add NativePayment() to VRFCoordinator_2x_Interface and integ tests

[vreff]

Sanity check for this PR: https://github.com/smartcontractkit/chainlink/pull/12085, which needed to be merged in quickly for a release deadline. Validates that the nativePayment component in RandomWordsFulfilled logs matches their corresponding values in requests.

[github-actions[bot]]

I see that you haven't updated any README files. Would it make sense to do so?

[cl-sonarqube-production[bot]]

Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

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