metrics: remove prometheus metrics collection.

Remove the original, now unused prometheus-based metrics
collection and remaining collectors.

Signed-off-by: Krisztian Litkey <[email protected]>

Author: klihub

go.mod

@@ -17,7 +17,6 @@ require (
 	github.com/onsi/gomega v1.35.1
 	github.com/pelletier/go-toml/v2 v2.1.0
 	github.com/prometheus/client_golang v1.23.0
-	github.com/prometheus/client_model v0.6.2
 	github.com/sirupsen/logrus v1.9.3
 	github.com/stretchr/testify v1.11.1
 	go.opentelemetry.io/otel v1.38.0
@@ -78,6 +77,7 @@ require (
 	github.com/opencontainers/runtime-spec v1.1.0 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
+	github.com/prometheus/client_model v0.6.2 // indirect
 	github.com/prometheus/common v0.65.0 // indirect
 	github.com/prometheus/otlptranslator v0.0.2 // indirect
 	github.com/prometheus/procfs v0.17.0 // indirect