[MM-16032] Add system ping endpoint health checks (#11267)

* Add system ping endpoint health checks

This change adds the option for additional server health checks
to be performed when the system ping endpoint is hit. An additional
field 'getserverstatus' is required to run the enhanced health
checks to ensure previous default ping behavior is not modified.

* Use snake_casing

services/filesstore/localstore.go

@@ -30,7 +30,7 @@ func (b *LocalFileBackend) TestConnection() *model.AppError {
 		return model.NewAppError("TestFileConnection", "api.file.test_connection.local.connection.app_error", nil, err.Error(), http.StatusInternalServerError)
 	}
 	os.Remove(filepath.Join(b.directory, TEST_FILE_PATH))
-	mlog.Info("Able to write files to local storage.")
+	mlog.Debug("Able to write files to local storage.")
 	return nil
 }
 

services/filesstore/s3store.go

@@ -79,7 +79,7 @@ func (b *S3FileBackend) TestConnection() *model.AppError {
 			return model.NewAppError("TestFileConnection", "api.file.test_connection.s3.bucked_create.app_error", nil, err.Error(), http.StatusInternalServerError)
 		}
 	}
-	mlog.Info("Connection to S3 or minio is good. Bucket exists.")
+	mlog.Debug("Connection to S3 or minio is good. Bucket exists.")
 	return nil
 }