JSON wizard: fix capitalization of message box title

Use book-style capitalization for titles.

Change-Id: I7912f63aeaa87ae5d562839edfafa584140b88e4
Reviewed-by: Tobias Hunger <tobias.hunger@theqtcompany.com>

src/plugins/projectexplorer/jsonwizard/jsonwizard.cpp

@@ -211,7 +211,7 @@ void JsonWizard::accept()
     emit filesReady(m_files);
     if (!JsonWizardGenerator::polish(this, &m_files, &errorMessage)) {
         if (!errorMessage.isEmpty())
-            QMessageBox::warning(this, tr("Failed to polish Files"), errorMessage);
+            QMessageBox::warning(this, tr("Failed to Polish Files"), errorMessage);
         return;
     }
     emit filesPolished(m_files);