Tidy array validation flow

Agent-Logs-Url: https://github.com/wesleyel/swiftui-math/sessions/56436444-e15b-4dd0-8a70-c87df1e3dc4e

Co-authored-by: wesleyel <48174882+wesleyel@users.noreply.github.com>

Sources/SwiftUIMath/Internal/Syntax/AtomFactory.swift

@@ -712,7 +712,7 @@ extension Math {
             return table
           }
         } else if env == "array" {
-          guard let columnAlignments, !columnAlignments.isEmpty else {
+          guard let columnAlignments else {
             let message = "array environment requires at least 1 column alignment"
             if error == nil {
               error = ParserError(code: .invalidEnvironment, message: message)