apply --match to image file names too, like we do for .skps

apply --match to image file names too, like we do for .skps

This should make skipping an image much cheaper.

Before:
   $ time out/Release/nanobench --images resources/ --match sdkjlfasjlfds
        4.65 real         4.41 user         0.19 sys
   $ time out/Release/nanobench --images resources/ --match sdkjlfasjlfds
        0.05 real         0.03 user         0.01 sys

The effect should be much more dramatic when there are more images to skip (e.g. on the bots).
This cuts about 6 minutes off the Debug CQ trybot.

BUG=skia:4768
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1577873002

Review URL: https://codereview.chromium.org/1577873002