DEV: Move spec/components to spec/lib (#15987)

Lib specs were inexplicably split into two directories (`lib` and `components`)

This moves them all into `lib`.

spec/lib/validators/group_setting_validator_spec.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe GroupSettingValidator do
+  describe '#valid_value?' do
+    subject(:validator) { described_class.new }
+
+    it "returns true for blank values" do
+      expect(validator.valid_value?('')).to eq(true)
+      expect(validator.valid_value?(nil)).to eq(true)
+    end
+
+    it "returns true if value matches an existing group" do
+      Fabricate(:group, name: "hello")
+      expect(validator.valid_value?('hello')).to eq(true)
+    end
+
+    it "returns false if value does not match a group" do
+      expect(validator.valid_value?('notagroup')).to eq(false)
+    end
+  end
+end