Apply brand defaults to MJML survey and product buttons

packages/email-renderer/src/mjml.ts

@@ -140,6 +140,9 @@ export function importMjml(
           } else if (defaults.tagName === "mj-text") {
             onlyAttributes(defaults, ["color"]);
             if (defaults.attributes?.color) brand.textColor = decode(defaults.attributes.color);
+          } else if (defaults.tagName === "mj-button") {
+            onlyAttributes(defaults, ["background-color"]);
+            if (defaults.attributes?.["background-color"]) brand.linkColor = decode(defaults.attributes["background-color"]);
           } else attributeError(defaults);
         }
       } else if (node.tagName === "mj-breakpoint") {