Bump github.com/open-telemetry/opentelemetry-collector-contrib/receiver/splunkhecreceiver from 0.106.1 to 0.111.0 in /functional_tests

Bump github.com/open-telemetry/opentelemetry-collector-contrib/receiver/splunkhecreceiver from 0.106.1 to 0.111.0 in /functional_tests #4342