Update N4A icon (#966)

chore: Update N4A icon

Author: lamATnginx

layouts/index.html

@@ -151,7 +151,7 @@ <h2 style="font-weight: 400; font-size: 1.5em; margin-top: 0px; margin-bottom: 0
             <div class="col-xs-12 col-sm-6 col-lg-4 card-holder">
                 <a href="{{ .Site.BaseURL }}nginxaas/azure" class="products-card" alt="NGINX as a Service for Azure">
                     <div class="saas-card">
-                        <div class="saas-icon"><img style="width: auto; height: auto;" src="{{ .Site.BaseURL }}/images/icons/NGINX-for-Azure-product-icon.png"></div>
+                        <div class="saas-icon"><img style="width: auto; height: auto;" src="{{ .Site.BaseURL }}/images/icons/NGINX-for-Azure-product-icon.svg"></div>
                         <div class="saas-description">
                             <h3 class="saas-title">NGINX as a Service for Azure</h3>
                             <p>Infrastructure-as-a-Service (IaaS) version of NGINX Plus for your Microsoft Azure application stack</p>
@@ -378,7 +378,7 @@ <h1 class="homepage-item-text">
         <div class="homepage-item">
             <div class="homepage-item-heading">
                 <div class="homepage-item-logo">
-                    <img class="card-img-top" src="{{ .Site.BaseURL }}/images/icons/NGINX-for-Azure-product-icon.png">
+                    <img class="card-img-top" src="{{ .Site.BaseURL }}/images/icons/NGINX-for-Azure-product-icon.svg">
                 </div>
                 <div class="homepage-item-text">
                     NGINX as a Service for Azure