perf: groth16 verifier circuit uses precomputed lines for all curves

[yelhousni]

Description

We forgot to update Groth16 verifier circuit to use NewG2AffineFixed for deltaNeg and gammaNeg in ValueOfVerifyingKeyFixed for all curves.

Type of change

• New feature (non-breaking change which adds functionality)

How has this been tested?

Tests in verifier_test.go in std/recursion/groth16 pass.

How has this been benchmarked?

(WIP: should benchmark for example bn254-over-bn254 and bn254-over-bw6-761)

Checklist:

• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I did not modify files generated from templates
• golangci-lint does not output errors locally
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[ivokub]

LGTM!