Refer to Datastore everywhere correctly by its capitalized form

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=147479683

java/google/registry/tools/server/KillAllCommitLogsAction.java

@@ -35,7 +35,7 @@ import google.registry.request.Response;
 import java.util.Arrays;
 import javax.inject.Inject;
 
-/** Deletes all commit logs in datastore. */
+/** Deletes all commit logs in Datastore. */
 @Action(path = "/_dr/task/killAllCommitLogs", method = POST)
 public class KillAllCommitLogsAction implements Runnable {