appstream: Check if categories are present

Only a handful of apps are missing this. These haven't received any activity in a long time.

This should not be breaking as compose requires categories to present already.

from lxml import etree

# curl -sL https://hub.flathub.org/repo/appstream/x86_64/appstream.xml.gz | gunzip -- > appstream.xml
components = etree.parse("appstream.xml").getroot()
for component in components.iterchildren(tag="component"):
   if component.attrib.get("type") not in ("desktop","desktop-application"):
        continue
   appstream_id = component.find("id").text
   category = component.xpath("categories")
   if not category:
      print(appstream_id)

List

``` app.drey.Damask cn.navclub.ldbfx com.arteeh.Flasher com.belmoussaoui.ashpd.demo com.github.HypatiaProject.hypatia com.github.appadeia.Taigo.desktop com.github.emmanueltouzery.cigale com.github.emmanueltouzery.hotwire com.github.emmanueltouzery.projectpad com.github.ojubaorg.Othman com.github.petebuffon.yafc com.github.sixpounder.GameOfLife com.github.theCalcaholic.StreamDeck com.gitlab.adnan338.Invoicer com.gitlab.adnan338.Nixwriter com.gitlab.maevemi.publictransport com.milesalan.mepo com.mudeprolinux.whakarere com.parallax.PropellerIDE com.ranfdev.Notify com.vixalien.sticky cool.ldr.lfy de.finnik.PassVault de.philippun1.Snoop.desktop de.wwwtech.ColorMate.desktop dev.salaniLeo.forecast dev.salaniLeo.immagini il.co.ravkavonline.RavKavOnline in.bharatkalluri.shortcircuit in.bharatkalluri.splash io.blockloader.BlockLoader io.github.FailurePoint.RandomNumberFive.desktop io.github.Sebicodes99.Prt io.github.chris2511.xca io.github.cloose.CuteMarkEd io.github.daviddesimone.opencloudsaves io.github.gssh_linux.gssh io.github.igaldino.CoyoteTM io.github.najepaliya.kleaner io.github.nokse22.trivia-quiz.desktop io.github.qwersyk.Newelle.desktop io.github.twanvl.MagicSetEditor2 io.github.zhrexl.thisweekinmylife io.gitlab.celleron56.libretile.desktop io.gitlab.cyberphantom52.sudoku_solver me.dusansimic.DynamicWallpaper me.hergert.Schemes.desktop me.iepure.Ticketbooth me.iepure.devtoolbox.desktop me.orszulak.keyring ml.mdwalters.Lemonade net.daase.journable net.danigm.loop.desktop net.lugsole.bible_gui.desktop net.sourceforge.QtSpim net.sourceforge.electrip.Electrip.desktop org.adishatz.syncpasswd.desktop org.gnome.design.VectorSlicer org.homelinuxserver.vance.biblereader org.jaspstats.JASP org.jjazzlab.JJazzLab org.mattdm.icebreaker org.pydpainter.PyDPainter page.codeberg.DrRac27.Karoto pm.mirko.Atoms.desktop pro.vpup.vpuppr ro.fxdata.taskmonitor.viewer xyz.aguno.CubeTimer xyz.ketok.Speedtest org.freedesktop.LinuxAudio.Plugins.SonoBus ```

flathub-infra / flatpak-builder-lint

appstream: Check if categories are present #374