Draft: Update Ironbank Docker tags

This MR contains the following updates:

Package	Update	Change
ironbank/elastic/elasticsearch/elasticsearch	patch	7.16.1 -> 7.16.3
ironbank/elastic/elasticsearch/elasticsearch	patch	7.16.2 -> 7.16.3
ironbank/elastic/kibana/kibana	patch	7.16.1 -> 7.16.2
registry1.dso.mil/ironbank/elastic/elasticsearch/elasticsearch	patch	7.16.1 -> 7.16.3
registry1.dso.mil/ironbank/elastic/kibana/kibana	patch	7.16.1 -> 7.16.2

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