Doc: Fix dead link in QCA::translate()

There's no 2nd translate() method. Instead, link to the section about
I18N in the summary.

Pick-to: 6.5
Change-Id: I7c3177cee91eeb550eb24b6f272a175b5c0e5487
Reviewed-by: Andreas Eliasson <andreas.eliasson@qt.io>

src/corelib/kernel/qcoreapplication.cpp

@@ -2281,7 +2281,8 @@ static void replacePercentN(QString *result, int n)
     This function is not virtual. You can use alternative translation
     techniques by subclassing \l QTranslator.
 
-    \sa QObject::tr(), installTranslator(), removeTranslator(), translate()
+    \sa QObject::tr(), installTranslator(), removeTranslator(),
+        {Internationalization and Translations}
 */
 QString QCoreApplication::translate(const char *context, const char *sourceText,
                                     const char *disambiguation, int n)