tools: if pytest fails to import, skip the tool option parsing test

It's not the most important test outside of my machine and CI, so let's just
skip over it.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Tested-by: Michel Dänzer <mdaenzer@redhat.com>

tools/test_tool_option_parsing.py

@@ -24,12 +24,18 @@
 # DEALINGS IN THE SOFTWARE.
 
 import os
-import pytest
 import resource
 import sys
 import subprocess
 import logging
 
+try:
+    import pytest
+except ImportError:
+    print('Failed to import pytest. Skipping.', file=sys.stderr)
+    sys.exit(77)
+
+
 logger = logging.getLogger('test')
 logger.setLevel(logging.DEBUG)