Contact: Update images, rename to follow new convention

src/_includes/contact.html

@@ -25,7 +25,7 @@ <h2 class="h1 text-center text-md-start d-block mb-3">The time is now—reach ou
     <div class="background-calitp-blue pt-3 pt-md-5 px-3 text-center clipped-end">
       <picture
         ><img
-          src="/images/connect.png"
+          src="/images/contact-connect.png"
           alt="Two thought bubbles with dashes of various lengths, meant to represent words in a conversation"
           width="105"
       /></picture>
@@ -47,7 +47,7 @@ <h3 class="text-white d-block my-4">Connect with Cal-ITP</h3>
     <div class="background-calitp-blue pt-3 pt-md-5 px-md-5 px-3 pt-2 text-center clipped-start">
       <picture
         ><img
-          src="/images/stay-up-to-date.png"
+          src="/images/contact-bus.png"
           alt="A bus nearly surrounded by a semicircular arrow, meant to indicate that transit content is being refreshed"
           width="86"
       /></picture>