fix: otlp doc + potential panic

docs/content/observability/tracing/overview.md

@@ -170,7 +170,6 @@ Defines the list of query parameters to not redact.
 
 ```yaml tab="File (YAML)"
 tracing:
-  otlp:
     safeQueryParams:
       - bar
       - buz
@@ -178,10 +177,9 @@ tracing:
 
 ```toml tab="File (TOML)"
 [tracing]
-  [tracing.otlp]
     safeQueryParams = ["bar", "buz"]
 ```
 
 ```bash tab="CLI"
---tracing.otlp.safeQueryParams=bar,buz
+--tracing.safeQueryParams=bar,buz
 ```

pkg/config/static/static_config.go

@@ -212,6 +212,9 @@ type Tracing struct {
 func (t *Tracing) SetDefaults() {
 	t.ServiceName = "traefik"
 	t.SampleRate = 1.0
+
+	t.OTLP = &opentelemetry.Config{}
+	t.OTLP.SetDefaults()
 }
 
 // Providers contains providers configuration.