Bump github.com/DataDog/agent-payload/v5 in /test/fakeintake

Bumps [github.com/DataDog/agent-payload/v5](https://github.com/DataDog/agent-payload) from 5.0.177 to 5.0.178.
- [Release notes](https://github.com/DataDog/agent-payload/releases)
- [Commits](DataDog/agent-payload@v5.0.177...v5.0.178)

---
updated-dependencies:
- dependency-name: github.com/DataDog/agent-payload/v5
  dependency-version: 5.0.178
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

test/fakeintake/go.mod

@@ -5,7 +5,7 @@ go 1.25.0
 // every datadog-agent module replaced in the fakeintake go.mod needs to be copied in the Dockerfile
 
 require (
-	github.com/DataDog/agent-payload/v5 v5.0.177
+	github.com/DataDog/agent-payload/v5 v5.0.178
 	github.com/DataDog/datadog-agent/comp/netflow/payload v0.56.0-rc.3
 	github.com/DataDog/datadog-agent/pkg/metrics v0.64.0
 	github.com/DataDog/datadog-agent/pkg/networkpath/payload v0.0.0-20250128160050-7ac9ccd58c07