Update amazon-workspaces.rb with caveats that it requires Rosetta

It does requires Rosetta on an Apple Silicon machine to run.

Casks/a/amazon-workspaces.rb

@@ -25,4 +25,8 @@ cask "amazon-workspaces" do
     "~/Library/Preferences/com.amazon.workspaces.plist",
     "~/Library/Saved Application State/com.amazon.workspaces.savedState",
   ]
+
+  caveats do
+    requires_rosetta
+  end
 end