Update README.md (open-telemetry#44419)

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Fixes

open-telemetry#44410

Author: khushijain21

receiver/redfishreceiver/README.md

@@ -60,7 +60,7 @@ receivers:
   redfish:
     collection_interval: 60s
     servers:
-    - host: https://16.1.15.1
+    - base_url: https://16.1.15.1
       username: "${BMC_USER}"
       password: "${BMC_PASSWORD}"
       insecure: true