Fixed duplicate initialization of OTel API

- I misread the docs here and didn't realise you shouldn't set up a
  provider and an SDK separately
- this fixes that by just switching to the SDK

src/instrumentation.ts

@@ -1,7 +1,7 @@
-import { CloudPropagator } from '@google-cloud/opentelemetry-cloud-trace-propagator';
 import {
     DiagConsoleLogger,
     DiagLogLevel,
+    type TextMapPropagator,
     diag,
     trace,
 } from '@opentelemetry/api';
@@ -10,20 +10,12 @@ import { NodeSDK } from '@opentelemetry/sdk-node';
 import {
     BatchSpanProcessor,
     SimpleSpanProcessor,
+    type SpanProcessor,
 } from '@opentelemetry/sdk-trace-base';
-import { NodeTracerProvider } from '@opentelemetry/sdk-trace-node';
 import * as Sentry from '@sentry/node';
 
-const sdk = new NodeSDK({
-    instrumentations: getNodeAutoInstrumentations({
-        '@opentelemetry/instrumentation-mysql2': {
-            addSqlCommenterCommentToQueries: true,
-        },
-    }),
-});
-
-const provider = new NodeTracerProvider();
-let propagator: CloudPropagator | undefined;
+let textMapPropagator: TextMapPropagator | undefined;
+const spanProcessors: SpanProcessor[] = [];
 
 if (process.env.NODE_ENV === 'production') {
     if (process.env.OTEL_DEBUG_LOGGING) {
@@ -37,17 +29,20 @@ if (process.env.K_SERVICE) {
     const { TraceExporter } = await import(
         '@google-cloud/opentelemetry-cloud-trace-exporter'
     );
-    provider.addSpanProcessor(new BatchSpanProcessor(new TraceExporter()));
+    spanProcessors.push(new BatchSpanProcessor(new TraceExporter()));
 
-    propagator = new CloudPropagator();
+    const { CloudPropagator } = await import(
+        '@google-cloud/opentelemetry-cloud-trace-propagator'
+    );
+    textMapPropagator = new CloudPropagator();
 }
 
 if (process.env.NODE_ENV === 'development') {
     const { OTLPTraceExporter } = await import(
         '@opentelemetry/exporter-trace-otlp-proto'
     );
 
-    provider.addSpanProcessor(
+    spanProcessors.push(
         new SimpleSpanProcessor(
             new OTLPTraceExporter({
                 url: 'http://jaeger:4318/v1/traces',
@@ -56,12 +51,18 @@ if (process.env.NODE_ENV === 'development') {
     );
 }
 
-provider.register({
-    propagator,
-});
-
 export const tracer = trace.getTracer('activitypub');
 
+const sdk = new NodeSDK({
+    instrumentations: getNodeAutoInstrumentations({
+        '@opentelemetry/instrumentation-mysql2': {
+            addSqlCommenterCommentToQueries: true,
+        },
+    }),
+    spanProcessors,
+    textMapPropagator,
+});
+
 try {
     sdk.start();
 } catch (e) {