update names of buttons

index.html

@@ -9,7 +9,7 @@
     <select id="configSelect">
         {{configs}}
     </select>
-    <button onclick="apply()">Apply</button>
+    <button onclick="apply()">Change track</button>
 
     <br><br>
 
@@ -20,7 +20,7 @@
 
     <h2>Choose cars</h2>
     <button id="addCarBtn">Add Car</button>
-    <button id="applyCarsBtn">Apply Cars</button>
+    <button id="applyCarsBtn">Change cars</button>
 
     <div id="carList"></div>