Refer to Datastore everywhere correctly by its capitalized form

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

java/google/registry/tools/GenerateEscrowDepositCommand.java

@@ -74,7 +74,7 @@ final class GenerateEscrowDepositCommand implements RemoteApiCommand {
 
   @Parameter(
       names = {"-w", "--watermark"},
-      description = "Point-in-time timestamp for snapshotting the datastore.",
+      description = "Point-in-time timestamp for snapshotting Datastore.",
       validateWith = DateTimeParameter.class)
   private DateTime watermark = DateTime.now(UTC);