extension-app: Improve appdata for AppStream 1.0

- Use the `<developer><name>` tag instead of the deprecated `<developer_name>`
- Implement appstreamcli for extra appdata validation
- Fix a release description
- Update the donation URL
- Add the translation tag

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/3071>

subprojects/extensions-app/data/metainfo/meson.build

@@ -8,9 +8,18 @@ i18n.merge_file(
 )
 
 if (appstream_util.found())
-  test('Validating ' + metainfo,
+  test('Validating via appstream_util ' + metainfo,
     appstream_util,
     args: ['validate', '--nonet', metainfo],
     workdir: meson.current_build_dir()
   )
 endif
+
+# Validate Appdata
+if (appstreamcli.found())
+  test('Validating ' + metainfo,
+    appstreamcli,
+    args: ['validate', '--no-net', metainfo],
+    workdir: meson.current_build_dir()
+  )
+endif

subprojects/extensions-app/data/metainfo/org.gnome.Extensions.metainfo.xml.in

@@ -10,13 +10,16 @@
 
   <url type="homepage">https://apps.gnome.org/Extensions/</url>
   <url type="bugtracker">https://gitlab.gnome.org/GNOME/gnome-shell/issues/new</url>
-  <url type="donation">http://www.gnome.org/friends/</url>
+  <url type="donation">https://www.gnome.org/donate/</url>
   <url type="translate">https://wiki.gnome.org/TranslationProject</url>
   <url type="vcs-browser">https://gitlab.gnome.org/GNOME/gnome-shell/-/tree/HEAD/subprojects/extensions-app</url>
 
   <project_group>GNOME</project_group>
-  <developer_name>The GNOME Project</developer_name>
+  <developer id="gnome.org">
+    <name>The GNOME Project</name>
+  </developer>
 
+  <translation type="gettext">gnome-extensions-app</translation>
   <launchable type="desktop-id">org.gnome.Extensions.desktop</launchable>
 
   <kudos>
@@ -45,7 +48,9 @@
 
   <releases>
     <release version="45.0" date="2023-09-16">
-      <p>Modernize layout</p>
+      <description>
+        <p>Modernize layout</p>
+      </description>
     </release>
   </releases>