Revert "Dependency: Update to Prometheus 0.300.* (open-telemetry#36873)" (#3)

This reverts commit af6b17e.

Author: cmacknz

connector/datadogconnector/go.sum

@@ -4,7 +4,6 @@ receivers:
       scrape_configs:
       - job_name: 'otelcol'
         scrape_interval: 10s
-        fallback_scrape_protocol: "PrometheusText1.0.0"
         static_configs:
         - targets: ['0.0.0.0:8888']
 

exporter/datadogexporter/examples/collector-metrics.yaml

@@ -39,7 +39,6 @@ receivers:
       scrape_configs:
       - job_name: 'otelcol'
         scrape_interval: 10s
-        fallback_scrape_protocol: "PrometheusText1.0.0"
         static_configs:
         - targets: ['0.0.0.0:8888']