Use git recordings when running make validate

[pquentin]

With the corresponding clients-flight-recorder pull request, this requires running make validate-no-cache instead of simply make validate. For example:

❯ make validate-no-cache api=xpack.info branch=main
Validating endpoints
Validating xpack.info
xpack.info request has been successfully validated!

✔ 8 out of 8 test request cases are passing.
✔ 4 out of 4 test response cases are passing.