Compositor: Increase tolerance for matte tests

The test is very susceptible to exact input values, and recent
change from Filmic to Standard view for those test changed values.

This change is similar to #110897

Pull Request: https://projects.blender.org/blender/blender/pulls/111339

tests/python/compositor_cpu_render_tests.py

@@ -63,7 +63,8 @@ def main():
         # input image. It makes it hard to precisely match results on different systems
         # (with and without SSE, i.e.), especially when OCIO has different precision for
         # the exponent transform on different platforms.
-        report.set_fail_threshold(0.05)
+        report.set_fail_threshold(0.06)
+        report.set_fail_percent(2)
 
     ok = report.run(test_dir, blender, get_arguments, batch=True)