docs: update the Call page

Update the Call page with some updated text and some product-specific
testimonials.

src/content/config.ts

@@ -53,9 +53,10 @@ const talkCollection = defineCollection({
 const testimonialCollection = defineCollection({
   type: 'data',
   schema: z.object({
+    date: z.string().optional(),
     image: z.string().or(z.null()),
     name: z.string(),
-    tagline: z.string(),
+    tagline: z.string().or(z.null()),
     text: z.string(),
     url: z.string().or(z.null()),
   }),

src/content/testimonial/michael-itkoff2.json

@@ -0,0 +1,8 @@
+{
+  "name": "Michael Itkoff",
+  "tagline": "Cofounder",
+  "url": "https://www.daylightbooks.org",
+  "text": "<p>Ollie handled the tech support issues efficiently and effectively, leaving time at the end for further troubleshooting and follow up. Much appreciated!</p>",
+  "image": "",
+  "date": "2023-07-13"
+}

src/content/testimonial/tom-evans.json

@@ -0,0 +1,9 @@
+
+{
+  "name": "Tom Evans",
+  "tagline": null,
+  "text": "<p>I had the opportunity and good fortune to work with Oliver solving two problems that I was having on a Drupal Commerce site.  I have done several Drupal sites using UberCart, but since it is deprecated, I chose to use Commerce.  I had searched, posted to forums, and other normal means to find answers to my problems, to no response and to no avail.</p><p>I got a referral to Oliver and scheduled an appointment to discuss the problems on a Zoom call.  After showing him via screen share where I was stumped, he offered different approaches to what I was doing, which I was fine with as long as it worked.</p><p>Once we solved the first problem, I was really elated and then focused on the second one, which was an easier fix.  So in a short period of time, both problems were fixed and tested.</p><p>I found Oliver was affable and easy to work with.  He has a strong work ethic and a desire to solve problems for his customers and can recommend working with him.  I think one of his strengths is to find alternative solutions to problems.</p>",
+  "image": null,
+  "url": null,
+  "date": "2023-07-14"
+}