Add autocomplete placeholder

app/frontend/controllers/accessible_autocomplete_controller.js

@@ -22,6 +22,7 @@ export default class extends Controller {
         }
       },
       autoselect: true,
+      placeholder: 'Start typing to search',
       templates: { suggestion: (value) => suggestion(value, options) },
       name: rawFieldName,
       onConfirm: (val) => {

spec/features/form/accessible_autocomplete_spec.rb

@@ -63,6 +63,10 @@ RSpec.describe "Accessible Autocomplete" do
       click_link(text: "Back")
       expect(page).to have_selector("input", class: "autocomplete__input", count: 1)
     end
+
+    it "displays the placeholder text", js: true do
+      expect(find("#lettings-log-prevloc-field")["placeholder"]).to eq("Start typing to search")
+    end
   end
 
   context "when searching schemes" do