The following errors are found during appdata checking:
* org.flameshot.flameshot: missing-desktop-file
* flameshot.desktop: no-metainfo
The root cause is the lack of a <launchable type="desktop-id"> tag
in the metainfo file that references the name of .desktop file.
This commit fixes that.
(Another solution would be renaming flameshot.desktop to be
org.flameshot.flameshot.desktop.)
42f6c8d501