Secure the ext-proc connect in epp

[ahg-g]

Specifically the grpc server we create at

gateway-api-inference-extension/pkg/ext-proc/main.go

Line 219 in 1c49986

svr := grpc.NewServer()

must be configured with a certificate

See example: https://github.com/GoogleCloudPlatform/service-extensions/blob/44fe708096efabadd3cb6fe30d6063a7f46fc9ea/callouts/go/extproc/internal/server/callout_server.go#L82

We can also create the certificate on the fly as we typically do for webhooks that we setup for CRDs, see example https://github.com/kubernetes-sigs/jobset/blob/c5f94e124d7bbf602baebc3ca3f4f25868f4791a/pkg/util/cert/cert.go#L51

[danehans]

@ahg-g Is this issue required for #73?

[ahg-g]

I prefer yes, will you be able to help with it and submit something today or tomorrow?

[danehans]

@ahg-g I assigned myself this issue and added it to the v0.1 meta issue.

[danehans]

Note that #222 is refactoring this section of the code.

[ahg-g]

I think we can delay this until after the first release if it is not yet ready as we will not recommend deploying this in any production setting for now.