tests: use FORCE flag to remove jail in tests

lib/includes

@@ -27,7 +27,7 @@ LOGLEVEL="${LOGLEVEL:-6}"
 CRITICAL="${CRITICAL:-48}"
 WARNING="${WARNING:-24}"
 DUC=$(command -v duc-nox || command -v duc)
-FORCE=0
+FORCE="${FORCE:-0}"
 
 show_version() {
     cat <<END

test/test_helper.bash

@@ -20,7 +20,7 @@ setup() {
 
 teardown() {
     remove_variable "/etc/default/bkctld" "BACKUP_DISK"
-    /usr/lib/bkctld/bkctld-remove "${JAILNAME}" && rm -rf "${INCSPATH}"
+    FORCE=1 /usr/lib/bkctld/bkctld-remove "${JAILNAME}" && rm -rf "${INCSPATH}"
 }
 
 random_jail_name() {