Fix minimum XWiki version on which the livetable exporter macro works

Today the declared dependencies of the extension are at version 6.0. However, I tried on 6.4.8 and I could not install any of the livetable exporter macro versions, as it has a dependency that is incompatible with the XWiki platform 6.4.8.
The job macro, that is a dependency since XALTXLS-23 , has a minimum compatibility with 7.4.4, so the new compatible version will be at least 7.4.4. However, since it's not the only blocking thing, the new minimum version may even be higher than this.