build_artifact: Be more specific when searching for full payloads

A recent CL (CL:1427346) broke the CQ because the devservers weren't
able to identify the actually payload from three file examples:

chromeos_R74-11727.0.0-rc1_bob_full_dev.bin
chromeos_R74-11727.0.0-rc1_bob_full_dev.bin.json
chromeos_R74-11727.0.0-rc1_bob_full_dev.bin.log

which are the files we need in future for applying payloads.

This CL, fixes the build_artifacts to be more specific by only searching
for files with regular expression *_full_*bin instead. That way it will
ignore the .json and .log files.

BUG=chromium:930290
TEST=start_devserver; curl 127.0.0.1:8080/xbuddy/remote/lakitu-st-paladin/R74-11727.0.0-rc1/full_payload

Change-Id: Ic04bce3361958c4cd57a7b4a38eee48c34a60683
Reviewed-on: https://chromium-review.googlesource.com/1470882
Commit-Ready: Amin Hassani <ahassani@chromium.org>
Tested-by: Amin Hassani <ahassani@chromium.org>
Reviewed-by: Congbin Guo <guocb@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
(cherry picked from commit e9596af0e75af8cb17e7124562c18181bcfd8f2e)
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/1516437
Commit-Queue: Keith Haddow <haddowk@chromium.org>
Tested-by: Keith Haddow <haddowk@chromium.org>
Trybot-Ready: Keith Haddow <haddowk@chromium.org>
diff --git a/build_artifact.py b/build_artifact.py
index e7e0514..502b739 100755
--- a/build_artifact.py
+++ b/build_artifact.py
@@ -614,7 +614,7 @@
   chromeos_artifact_map.setdefault(tag, []).append(artifact)
 
 
-_AddCrOSArtifact(artifact_info.FULL_PAYLOAD, AUTestPayload, '*_full_*')
+_AddCrOSArtifact(artifact_info.FULL_PAYLOAD, AUTestPayload, '*_full_*bin')
 
 
 class DeltaPayloadNtoN(DeltaPayloadBase):