[DI] Improve logging in integration tests (#5610)

The Dynamic Instrumentation integration tests uses Fastify in some of
the instrumented test apps.

We've seen issues in CI where the inspected application exits with exit
code 1, but there's no error message being logged. So it's not possible
to see what caused the process to exit.

By default Fastify doesn't log any messages to STDOUT/STDERR. This might
be the reason why we only see the exit code, but not any error message.

For better visibility into such errors in CI, this commit changes the
default log level to `error`, so that errors are logged to STDERR.

Author: watson

integration-tests/debugger/target-app/basic.js

@@ -3,7 +3,7 @@
 require('dd-trace/init')
 const Fastify = require('fastify')
 
-const fastify = Fastify()
+const fastify = Fastify({ logger: { level: 'error' } })
 
 fastify.get('/foo/:name', function fooHandler (request) {
   return { hello: request.params.name } // BREAKPOINT: /foo/bar

integration-tests/debugger/target-app/redact.js

@@ -3,7 +3,7 @@
 require('dd-trace/init')
 const Fastify = require('fastify')
 
-const fastify = Fastify()
+const fastify = Fastify({ logger: { level: 'error' } })
 
 fastify.get('/', function () {
   /* eslint-disable no-unused-vars */

integration-tests/debugger/target-app/snapshot-pruning.js

@@ -5,7 +5,7 @@ require('dd-trace/init')
 const { randomBytes } = require('crypto')
 const Fastify = require('fastify')
 
-const fastify = Fastify()
+const fastify = Fastify({ logger: { level: 'error' } })
 
 const TARGET_SIZE = 1024 * 1024 // 1MB
 const LARGE_STRING = randomBytes(1024).toString('hex')

integration-tests/debugger/target-app/snapshot.js

@@ -3,7 +3,7 @@
 require('dd-trace/init')
 const Fastify = require('fastify')
 
-const fastify = Fastify()
+const fastify = Fastify({ logger: { level: 'error' } })
 
 fastify.get('/:name', function handler (request) {
   /* eslint-disable no-unused-vars */

integration-tests/debugger/target-app/template.js

@@ -4,7 +4,7 @@ require('dd-trace/init')
 const { inspect } = require('util')
 const Fastify = require('fastify')
 
-const fastify = Fastify()
+const fastify = Fastify({ logger: { level: 'error' } })
 
 const weakObj = {}