functions: set flag "REDMINE_WAS_UPDATED" when a redmine-upgrade was …

…done

Set the variable REDMINE_WAS_UPDATED=yes when the redmine-version was upgraded.
This flag can be evaluated later, e.g. inside entrypoint.custom.sh

assets/runtime/functions

@@ -1058,6 +1058,7 @@ migrate_database() {
 
     # Now that database has been migrated, update version file
     echo ${REDMINE_VERSION} | exec_as_redmine tee --append ${REDMINE_DATA_DIR}/tmp/VERSION >/dev/null
+    export REDMINE_WAS_UPDATED=yes
   fi
 }