fix linting error

Author: c1ly

tools/pipeline_perf_test/test_suites/integration/nightly/otelcol-docker.yaml

@@ -93,4 +93,4 @@ tests:
       variables:
         collector_config_template: test_suites/integration/templates/configs/otelcol/otap-filter-otap.yaml
         loadgen_exporter_type: otap
-        backend_receiver_type: otap
+        backend_receiver_type: otap