Update Apollo OTLP endpoint and improve debug messages a little. (#3641)

Update Apollo OTLP endpoint to the final prod value


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**Checklist**

Complete the checklist (and note appropriate exceptions) before a final
PR is raised.

- [ ] Changes are compatible[^1]
- [ ] Documentation[^2] completed
- [ ] Performance impact assessed and acceptable
- Tests added and passing[^3]
    - [ ] Unit Tests
    - [ ] Integration Tests
    - [ ] Manual Tests

**Exceptions**

*Note any exceptions here*

**Notes**

[^1]. It may be appropriate to bring upcoming changes to the attention
of other (impacted) groups. Please endeavour to do this before seeking
PR approval. The mechanism for doing this will vary considerably, so use
your judgement as to how and when to do this.
[^2]. Configuration is an important part of many changes. Where
applicable please try to document configuration examples.
[^3]. Tick whichever testing boxes are applicable. If you are adding
Manual Tests:
- please document the manual testing (extensively) in the Exceptions.
- please raise a separate issue to automate the test and label it (or
ask for it to be labeled) as `manual test`

---------

Co-authored-by: bryn <[email protected]>

apollo-router/src/configuration/snapshots/apollo_router__configuration__tests__schema_generation.snap

@@ -2054,7 +2054,7 @@ expression: "&schema"
             },
             "experimental_otlp_endpoint": {
               "description": "The Apollo Studio endpoint for exporting traces and metrics.",
-              "default": "http://0.0.0.0:4317/",
+              "default": "https://usage-reporting.api.apollographql.com/",
               "type": "string"
             },
             "field_level_instrumentation_sampler": {

apollo-router/src/plugins/telemetry/apollo.rs

@@ -33,7 +33,7 @@ use crate::services::apollo_key;
 pub(crate) const ENDPOINT_DEFAULT: &str =
     "https://usage-reporting.api.apollographql.com/api/ingress/traces";
 
-pub(crate) const OTLP_ENDPOINT_DEFAULT: &str = "http://0.0.0.0:4317";
+pub(crate) const OTLP_ENDPOINT_DEFAULT: &str = "https://usage-reporting.api.apollographql.com";
 
 #[derive(Derivative)]
 #[derivative(Debug)]

apollo-router/src/plugins/telemetry/metrics/apollo.rs

@@ -94,7 +94,7 @@ impl Config {
         schema_id: &str,
         batch_processor: &BatchProcessorConfig,
     ) -> Result<MetricsBuilder, BoxError> {
-        tracing::debug!("creating otlp metrics exporter");
+        tracing::debug!(endpoint = %endpoint, "creating Apollo OTLP metrics exporter");
         let mut metadata = MetadataMap::new();
         metadata.insert("apollo.api.key", key.parse()?);
 
@@ -142,7 +142,7 @@ impl Config {
         batch_processor: &BatchProcessorConfig,
     ) -> Result<MetricsBuilder, BoxError> {
         let batch_processor_config = batch_processor;
-        tracing::debug!("creating metrics exporter");
+        tracing::debug!(endpoint = %endpoint, "creating Apollo metrics exporter");
         let exporter =
             ApolloExporter::new(endpoint, batch_processor_config, key, reference, schema_id)?;