fix Activity 3 EQ instruction to match actual button label

Author: espadonne

lib/activity/activityConfigs.js

@@ -157,7 +157,7 @@ export const ACTIVITY_3_CONFIG = {
       title: 'Part 3: Applying EQ',
       items: [
         'Select a clip on one of your tracks by clicking on it.',
-        'Click the effects button (sparkle icon) in the toolbar to open the effects rack.',
+        'Click the "Effects" button in the toolbar to open the effects rack.',
         'Click "Add Effect" and select "Equalizer" from the list.',
         'Click on the equalizer effect you just added to open its parameters.',
         'In the EQ view, find the "EQ Preset" dropdown and select "Warm Bass".',