feat(contented-preview): add table-auto and table-fixed support (#550)

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#### What this PR does / why we need it:

As per title.

packages/contented-preview/src/styles/prose.css

@@ -52,3 +52,13 @@
   @apply border-slate-200/70 bg-slate-100/70 text-slate-800;
   @apply dark:border-slate-700/70 dark:bg-slate-800/70 dark:text-slate-200;
 }
+
+.prose .table-auto table {
+  display: table;
+  table-layout: auto;
+}
+
+.prose .table-fixed table {
+  display: table;
+  table-layout: fixed;
+}