Tests: Make environment test less verbose

Only print out additional information if the environment
does not match the expected one.

Change-Id: I9be1a90400a180a4cbd0381f54eea79409c007c7
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

tests/auto/environment/tst_environment.cpp

@@ -377,9 +377,12 @@ void tst_Environment::pathChanges()
     else
         environment.appendOrSet(variable, value);
 
+    const bool envEqualsExpected = environment == expected;
+    if (!envEqualsExpected) {
         qDebug() << "Actual  :" << environment.toStringList();
         qDebug() << "Expected:" << expected.toStringList();
-    QCOMPARE(environment, expected);
+    }
+    QVERIFY(envEqualsExpected);
 }
 
 void tst_Environment::find_data()