README: fix typo in configuration key name (#203)
README: fix typo in configuration key name (#203)


open-telemetry/opentelemetry-collector,census-instrumentation/opencensus-service,census-instrumentation/opencensus-service,open-telemetry/opentelemetry-collector-contrib,open-telemetry/opentelemetry-collector,open-telemetry/opentelemetry-collector-contrib,open-telemetry/opentelemetry-collector