Update solr Docker tag to v9.6.1

This MR contains the following updates:

Package	Type	Update	Change
solr		patch	9.6.0 -> 9.6.1
solr	ironbank-docker	patch	9.6.0-slim -> 9.6.1-slim
solr	stage	patch	9.6.0-slim -> 9.6.1-slim

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