fix html validator error

pages/widgets.html

@@ -3085,7 +3085,7 @@
             <div class="row">
               <div class="col-md-12 col-lg-6 col-xl-4">
                 <div class="card mb-2 bg-gradient-dark">
-                  <img class="card-img-top" src="../dist/img/photo1.png">
+                  <img class="card-img-top" src="../dist/img/photo1.png" alt="Dist Photo 1">
                   <div class="card-img-overlay d-flex flex-column justify-content-end">
                     <h5 class="card-title text-primary text-white">Card Title</h5>
                     <p class="card-text text-white pb-2 pt-1">Lorem ipsum dolor sit amet, consectetur adipisicing elit sed do eiusmod tempor.</p>
@@ -3095,7 +3095,7 @@
               </div>
               <div class="col-md-12 col-lg-6 col-xl-4">
                 <div class="card mb-2">
-                  <img class="card-img-top" src="../dist/img/photo2.png">
+                  <img class="card-img-top" src="../dist/img/photo2.png" alt="Dist Photo 2">
                   <div class="card-img-overlay d-flex flex-column justify-content-center">
                     <h5 class="card-title text-white mt-5 pt-2">Card Title</h5>
                     <p class="card-text pb-2 pt-1 text-white">
@@ -3109,7 +3109,7 @@
               </div>
               <div class="col-md-12 col-lg-6 col-xl-4">
                 <div class="card mb-2">
-                  <img class="card-img-top" src="../dist/img/photo3.jpg">
+                  <img class="card-img-top" src="../dist/img/photo3.jpg" alt="Dist Photo 3">
                   <div class="card-img-overlay">
                     <h5 class="card-title text-primary">Card Title</h5>
                     <p class="card-text pb-1 pt-1 text-white">