Update Ironbank Docker tags to v7.16.1

This MR contains the following updates:

Package	Update	Change
ironbank/elastic/elasticsearch/elasticsearch	minor	7.14.1 -> 7.16.1
ironbank/elastic/kibana/kibana	minor	7.14.0 -> 7.16.1
registry1.dso.mil/ironbank/elastic/elasticsearch/elasticsearch	minor	7.14.1 -> 7.16.1
registry1.dso.mil/ironbank/elastic/kibana/kibana	minor	7.14.0 -> 7.16.1

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