Update our Confluence Page Gadget documentation

Problem statement

According to this page, we ended support for the Confluence Page gadget in Confluence 7.0.

This, however, does not apply to the Confluence Page Gadget on Jira, as it keeps working normally on Confluence 7.x versions. The documentation is not clear about that, and might give the impression that customers will need to use another gadget to reference Confluence pages on Jira, and this is not accurate.

Suggest resolution

Please make the documentation more clear, as the Confluence page gadget is still available for Jira and is the only option to reference pages from Confluence.