Use GRPC to report Elixir metrics

elixir/config/runtime.exs

@@ -126,6 +126,7 @@ if config_env() == :prod do
 
     config :opentelemetry_exporter,
       otlp_protocol: :http_protobuf,
+      otlp_traces_protocol: :http_protobuf,
       otlp_endpoint: System.get_env("OTLP_ENDPOINT")
   end
 

terraform/modules/elixir-app/main.tf

@@ -31,7 +31,7 @@ locals {
     },
     {
       name  = "OTLP_ENDPOINT",
-      value = "127.0.0.1:4317"
+      value = "127.0.0.1:4318"
     }
   ], var.application_environment_variables)