tst_qsslsocket - re-structure the code

setEmptyDefaultConfiguration - this test (and this was stated explicitly
in comments!) must be the last test to run, otherwise, it can make subsequent
tests fail.

-exitLoop must be in 'protected slots' section not to be executed as a test,
since ... it's aux function, not a test.

Task-number: QTBUG-53608
Task-number: QTBUG-53603
Change-Id: I49d6d57ba927ecc4f20ae2d9325ad02fa46b0922
Reviewed-by: Tony Sarajärvi <tony.sarajarvi@qt.io>

tests/auto/network/ssl/qsslsocket/tst_qsslsocket.cpp

@@ -222,7 +222,6 @@ private slots:
     void ecdhServer();
     void verifyClientCertificate_data();
     void verifyClientCertificate();
-    void setEmptyDefaultConfiguration(); // this test should be last
 
 #ifndef QT_NO_OPENSSL
     void simplePskConnect_data();
@@ -231,6 +230,10 @@ private slots:
     void ephemeralServerKey();
 #endif
 
+    void setEmptyDefaultConfiguration(); // this test should be last
+
+protected slots:
+
     static void exitLoop()
     {
         // Safe exit - if we aren't in an event loop, don't
@@ -241,7 +244,6 @@ private slots:
         }
     }
 
-protected slots:
     void ignoreErrorSlot()
     {
         socket->ignoreSslErrors();