Fix paths to subprocesses when test is run from other directory

Now it's possible to run the test outside of directory
where the test is located.

Change-Id: I2a2c693d382917ac7b84488c8ccf161538b58238
Reviewed-by: hjk <hjk@qt.io>
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

tests/auto/utils/qtcprocess/tst_qtcprocess.cpp

@@ -105,7 +105,8 @@ static CommandLine subCommandLine()
 {
     QStringList args = QCoreApplication::arguments();
     const QString binary = args.takeFirst();
-    return CommandLine(FilePath::fromString(binary), args);
+    const FilePath filePath = FilePath::fromString(QDir::currentPath()).resolvePath(binary);
+    return CommandLine(filePath, args);
 }
 
 class SubCreatorConfig