fix: workflow note editor placeholder (#14380)

web/app/components/workflow/note-node/index.tsx

             )}></div>
           {
             data.selected && (
-              <div className='absolute -top-[41px] left-1/2 -translate-x-1/2'>
+              <div className='absolute top-[-41px] left-1/2 -translate-x-1/2'>
                 <NoteEditorToolbar
                   theme={theme}
                   onThemeChange={handleThemeChange}

web/app/components/workflow/note-node/note-editor/editor.tsx

               onBlur={() => setShortcutsEnabled(true)}
               spellCheck={false}
               className='w-full h-full outline-none text-text-secondary caret-primary-600'
-              placeholder={placeholder}
             />
           </div>
         }