container: finance: lib_fetch: fix Tor plugin (proxychains) check

This ensures that curl will only be executed if the Tor plugin
(proxychains) argument is enabled.

container/src/finance/lib/internal/lib_fetch.bash

@@ -834,8 +834,10 @@ function lib_fetch::__fetch_exec()
   [[ "$global_arg_tor" =~ ^on$|^true$ ]] && _exec+=("proxychains") # Wrap with proxychains
 
   # Test for Tor plugin
-  if ! "${_exec[@]}" curl -s "https://check.torproject.org" &>/dev/null; then
-    lib_utils::die_fatal "Tor plugin not started (or needs restart)"
+  if [ ! -z "${_exec[*]}" ]; then
+    if ! "${_exec[@]}" curl -s "https://check.torproject.org" &>/dev/null; then
+      lib_utils::die_fatal "Tor plugin not started (or needs restart)"
+    fi
   fi
 
   # TODO: remove no-limit after internal fetching writes per-paginated instead of per-fetch