[PATCH] comdlg32/tests: Use GetTempPathA() instead of the current directory in test_extension().

[Marvin]

Hi,

While running your changed tests, I think I found new failures.
Being a bot and all I'm not very good at pattern recognition, so I might be
wrong, but could you please double-check?

Full results can be found at:
https://testbot.winehq.org/JobDetails.pl?Key=63239

Your paranoid android.


=== wvistau64 (32 bit report) ===

comdlg32:
filedlg.c:1040: Test failed: TestFilter (*.abc;): expected TRUE
filedlg.c:1046: Test failed: TestFilter (*.abc;): Filename is deadbeef, expected deadbeef.abc

Report errors:
comdlg32:filedlg crashed (c0000005)

=== w1064v1809_he (32 bit report) ===

comdlg32:
filedlg.c:1183: Test failed: GetOpenFileNameA returned 0