macOS: Make sure that the reserved characters are not escaped

The URL for the PAC proxy that is passed needs to be preserved for the
main URL part and not entirely percent encoded, only the query part
typically needs to be encoded. So use toEncoded instead for a URL to
ensure they are not percent encoded. This amends
c163ec1dbf

Pick-to: 6.0 5.15
Change-Id: Ie41ab55f71be8e25c18775e61ce7b4d110c2ddbf
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

src/network/kernel/qnetworkproxy_mac.cpp

@@ -208,7 +208,7 @@ QCFType<CFStringRef> stringByAddingPercentEscapes(CFStringRef originalPath)
 {
     Q_ASSERT(originalPath);
     const auto qtPath = QString::fromCFString(originalPath);
-    const auto escaped = QString::fromUtf8(QUrl::toPercentEncoding(qtPath));
+    const auto escaped = QString::fromUtf8(QUrl(qtPath).toEncoded());
     return escaped.toCFString();
 }