fix(rosetta): diagnostics not showing (#3182)

One-liner to make sure that we slice `diags` correctly. Tested locally on my own machine to ensure that it works.

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[Apache 2.0 license]: https://www.apache.org/licenses/LICENSE-2.0

packages/jsii-rosetta/lib/util.ts

@@ -15,7 +15,7 @@ export function printDiagnostics(diags: readonly RosettaDiagnostic[], stream: No
   // Don't print too much, at some point it just clogs up the log
   const maxDiags = 50;
 
-  for (const diag of diags.slice(maxDiags)) {
+  for (const diag of diags.slice(0, maxDiags)) {
     stream.write(diag.formattedMessage);
   }