fix(ui): fix placeholders for consistency (#1949)

frontend/app/components/FFlags/FFlagsSearch.tsx

@@ -33,7 +33,7 @@ function FFlagsSearch() {
         value={query}
         name="flagsSearch"
         className="bg-white p-2 border border-borderColor-gray-light-shade rounded w-full pl-10"
-        placeholder="Search by key"
+        placeholder="Filter by key"
         onChange={write}
       />
     </div>

frontend/app/components/UsabilityTesting/LiveTestsModal.tsx

@@ -33,7 +33,7 @@ function LiveTestsModal({ testId, closeModal }: { testId: string; closeModal: ()
         <div className={'w-3/4 font-semibold text-xl'}>Live Participants</div>
         <Input.Search
           allowClear
-          placeholder="Search by participant ID or name"
+          placeholder="Filter by participant ID or name"
           onChange={(e) => setUserId(e.target.value)}
           onSearch={() => refreshData(page)}
         />