Fix Windows tests within CMake

tests/pq_test.bat

@@ -2,13 +2,14 @@
 setlocal enabledelayedexpansion
 REM	pq_test.bat
 
-set TEST=Debug\pq_test.exe
-if not exist %TEST% exit /b 1
+set pq_test_bin=%1
+set pq_test_bin=%pq_test_bin:/=\%
+if not exist %pq_test_bin% exit /b 1
 
 set pq_output=pq_output.txt
 if exist %pq_output% del %pq_output%
 
-%TEST% > %pq_output%
+%pq_test_bin% > %pq_output%
 fc /b %pq_output% %srcdir%\pq_expected.txt
 
 endlocal