Snap: Change version-script to adopt-info to fix dirty.

https://forum.snapcraft.io/t/dirty-snap-release/12975/4

Thanks to popey and daniel at Snapcraft forum.

snapcraft.yaml

@@ -1,6 +1,5 @@
 name: wekan
 version: 0
-version-script: git describe --dirty --tags |  cut -c 2-
 summary: The open-source kanban
 description: |
    Wekan is an open-source and collaborative kanban board application.
@@ -221,7 +220,7 @@ parts:
             rm -f $SNAPCRAFT_PART_INSTALL/lib/node_modules/node-gyp/node_modules/tar/lib/.mkdir.js.swp
             # Meteor 1.8.x additional .swp remove
             rm -f $SNAPCRAFT_PART_INSTALL/programs/server/node_modules/node-pre-gyp/node_modules/tar/lib/.mkdir.js.swp
-
+        adopt-info: snapcraftctl set-version $(git describe --dirty --tags | cut -c 2-)
         organize:
             README: README.wekan
         prime: