fix: disable `require-image-signature` policy

Package Merge Request

Package Changes

Decided to not enable image-signature verification by default for now.

We'll need to make sure we have sufficient egress policies in place that ideally don't open up too much. We could also implement this issue: big-bang/product/packages/kyverno-policies#9 (closed) which set the failurePolicy to ignore where we only audit or warn on a policy. A failurePolicy of ignore would not prevent installs in the event of an i/o timeout where the policy is in audit or warn

Package MR

(Link to Package MR here)

For Issue

Closes (#1821 (closed))