Roll SK Tool from 87274fcd2b55 to 7159a93d57df

https://skia.googlesource.com/buildbot.git/+log/87274fcd2b55..7159a93d57df

2021-07-27 rmistry@google.com [skcq] Detect and post a better comment when merge conflicts occur

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/sk-tool-skia
Please CC jcgregorio@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md

Tbr: jcgregorio@google.com
Change-Id: I756952b9b6dfea7ee50fcca10faf1833c36efd1d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/432694
Reviewed-by: skia-autoroll <skia-autoroll@skia-public.iam.gserviceaccount.com>
Commit-Queue: skia-autoroll <skia-autoroll@skia-public.iam.gserviceaccount.com>
diff --git a/DEPS b/DEPS
index 65072fd..6a0a491 100644
--- a/DEPS
+++ b/DEPS
@@ -6,7 +6,7 @@
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling different
   # dependencies without interference from each other.
-  'sk_tool_revision': 'git_revision:74c0e4d78b6be89ef1cf34d7e08671155b53ab63',
+  'sk_tool_revision': 'git_revision:7159a93d57df49fddbf89a6345c5f92133174f2a',
 }
 
 deps = {