client: docker-finance.d: fetch: re-add docker-finance version tag

This was originally removed because it lacked functional usage, as there
already exists a 'version' key.

However, for consistency across all .in files, adding a version *tag*
(non-YAML) serves to quickly indentify what program this configuration
file actually belongs to.

client/docker-finance.d/container/fetch/fetch.yaml.in

@@ -15,6 +15,8 @@
 # You should have received a copy of the GNU General Public License
 # along with this program. If not, see <https://www.gnu.org/licenses/>.
 
+# docker-finance @DOCKER_FINANCE_VERSION@
+
 #
 # Configuration for `fetch` command
 #