Rename org.kde.minuet.appdata.xml to org.kde.minuet.metainfo.xml

https://freedesktop.org/software/appstream/docs/chap-Metadata.html#spec-component-location says "Note Component metadata of type desktop-application as described in Section 2.3, “Desktop Applications” can be installed with an .appdata.xml extension as well for historical reasons. AppStream implementations will read the XML files as long as they end up in the right location on the filesystem.".