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/env/common/default/WEB-INF/queue.xml

@@ -37,7 +37,7 @@
     <bucket-size>100</bucket-size>
     <retry-parameters>
       <!-- Retry aggressively since a single delayed export increases our time window of
-           unrecoverable data loss in the event of a datastore failure. -->
+           unrecoverable data loss in the event of a Datastore failure. -->
       <min-backoff-seconds>1</min-backoff-seconds>
       <max-backoff-seconds>60</max-backoff-seconds>
       <!-- No age limit; a failed export should be retried as long as possible to avoid