* caddyhttp: Escaping placeholders in CEL
* Simplify some of the test cases
* Implement vars and vars_regexp in CEL
* dupl lint is dumb
* Better consts for the placeholder CEL shortcut
* Bump CEL version, register a few extensions
* Refactor s390x test script for readability
* Add retries for s390x to smooth over flakiness
* Switch to `ph` for the CEL shortcut (match it in templates cause why not)
* caddyfile: Populate regexp matcher names by default
* Some lint cleanup that my VSCode complained about
* Pass down matcher name through expression matcher
* Compat with #6113: fix adapt test, set both styles in replacer
* cel: fix validation of expression result type
The earlier code used the proto.Equals from github.com/gogo/protobuf, which failed to compare two messages of the same type for some reason. Switching to proto.Equal from the canonical github.com/golang/protobuf fixes the issue.
* deps: remove deprecated github.com/golang/protobuf in favor of google.golang.org/protobuf
* downgrade github.com/smallstep/nosql to resolve warning pb.proto warning
