#195 Updated plugin for compatibility with OF 4.7.0

[evdherberg]

See #195 for details.

[guusdk]

Before we release a plugin, we should update the dependency in the pom.xml to a non-snapshot of Openfire 4.7.0 (which currently is not available yet).

[guusdk]

Does this change mean that the resulting plugin is no longer compatible with versions of Openfire prior to version 4.7.0? If so, we should update the value of <minServerVersion>4.4.0</minServerVersion> in plugin.xml to 4.7.0.

[evdherberg]

Does this change mean that the resulting plugin is no longer compatible with versions of Openfire prior to version 4.7.0? If so, we should update the value of <minServerVersion>4.4.0</minServerVersion> in plugin.xml to 4.7.0.

I think it does mean that. Let me take care of that.

[guusdk]

@akrherz is the Github Actions build failing similar to the issue that we've seen before? And if it is, does that mean it'll affect all plugins?

[akrherz]

Attempted to rebase this with my CI fix in place.

[guusdk]

CI seems happy!