Update dependency DataDog/dd-apm-inject to v0.68.0-1 (#53616)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| DataDog/dd-apm-inject | minor | `0.67.2-1` → `0.68.0-1` |

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Co-authored-by: devflow.devflow-routing-intake <devflow.devflow-routing-intake@kubernetes.us1.ddbuild.io>

Author: renovate[bot]

test/new-e2e/tests/installer/unix/package_definitions.go

@@ -88,7 +88,7 @@ func pinnedApmInjectVersion() string {
 	if version, ok := os.LookupEnv("E2E_APM_INJECT_PACKAGE_VERSION"); ok && version != "" {
 		return version
 	}
-	return "0.67.2-1"
+	return "0.68.0-1"
 }
 
 func previousApmInjectVersion() string {