appdata: translate=no properties

It appears that the appstream project no longer supports
`translatable=no` properties, and gettext extract them as translatable.

I opened an issue to inform about the situation, but `translatable=no`
properties are not accepted by developers. You can find the issue
here: `ximion/appstream#623

**Please test your script or string extraction process before merging this PR.**

> In MetaInfo files, each individual paragraph of a description
> (or enumerated entry) is translated individually, however,
> you can only exclude the complete block from being translated
> by adding `translate="no"` to the description element.

Source: https://freedesktop.org/software/appstream/docs/sect-Quickstart-Translation.html

data/org.freedesktop.fwupd.metainfo.xml

@@ -26,8 +26,8 @@
   <url type="vcs-browser">https://github.com/fwupd/fwupd</url>
   <update_contact>richard_at_hughsie.com</update_contact>
   <developer_name>The fwupd authors</developer_name>
-    <name translatable="no">The fwupd authors</name>
   <developer id="org.fwupd">
+    <name translate="no">The fwupd authors</name>
   </developer>
   <translation type="gettext">fwupd</translation>
   <content_rating type="oars-1.1">