fix: wait for unprepare() to complete before closing connection

The test was calling close() immediately after unprepare(), which would
cancel the unprepare operation. Now the test properly waits for the
unprepare requestCompleted event before closing the connection.

Co-authored-by: Arthur Schreiber <arthurschreiber@users.noreply.github.com>

Author: github-actions[bot]

test/integration/prepare-execute-statements-test.ts

@@ -195,9 +195,11 @@ describe('Prepare Execute Statement', function() {
             executionCount++;
             errors.push(request.error);
 
-            // Unprepare and close
+            // Unprepare the statement and wait for it to complete before closing
+            request.once('requestCompleted', function() {
+              connection.close();
+            });
             connection.unprepare(request);
-            connection.close();
           });
 
           connection.execute(request, { divisor: 2 });