chore: Upgrade caddy to v2.6.4

[Embraser01]

No description provided.

[francislavoie]

We're at v2.6.4 now. Maybe this should get updated and bumped

[Embraser01]

Just tried to upgrade to latest version of caddy and stumbled on an issue due to glog.
We have a deep dep that define the v flag and cause a panic when we defined our own v flag.

# go mod why gives this:
# github.com/golang/glog
github.com/caddyserver/ingress/internal/caddy/global
github.com/caddyserver/caddy/v2/modules/caddytls
github.com/caddyserver/caddy/v2/modules/caddypki
github.com/smallstep/certificates/authority
github.com/smallstep/nosql
github.com/smallstep/nosql/badger/v1
github.com/dgraph-io/badger
github.com/dgraph-io/ristretto/z
github.com/golang/glog

I'll just rename the flag for now (those using helm will not have to change anything, others may have to change. Because it's not something that should be enabled in a "production" env, I don't think it's a big issue).