configure conform also using the global variable

lua/lazyvim/plugins/extras/lang/ruby.lua

@@ -50,6 +50,16 @@ return {
       end,
     },
   },
+  {
+    "stevearc/conform.nvim",
+    optional = true,
+    opts = {
+      formatters_by_ft = {
+        ruby = { formatter },
+        eruby = { "erb-format" },
+      },
+    },
+  },
   {
     "nvim-neotest/neotest",
     optional = true,