DEPS: roll depot_tools

Rolling v8/third_party/depot_tools:
https://chromium.googlesource.com/chromium/tools/depot_tools/+log/2b2aec6..dd2f620

The roller is blocked since a few weeks, but we need this roll now to
fix a depot_tools version mismatch between the presubmit bots on CQ and
on the waterfall.

R=zhin@chromium.org
TBR=machenbach@chromium.org,tmrts@chromium.org
NOTREECHECKS=true

Bug: chromium:1075618
Change-Id: Ib3e4b2ad4d79a1b35db1b320c7f7aa682b1eab90
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2166198
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67404}

DEPS

@@ -74,7 +74,7 @@ deps = {
   'v8/build':
     Var('chromium_url') + '/chromium/src/build.git' + '@' + '26e9d485d01d6e0eb9dadd21df767a63494c8fea',
   'v8/third_party/depot_tools':
-    Var('chromium_url') + '/chromium/tools/depot_tools.git' + '@' + '2b2aec6506a810f8d7bd018609de2c2450b3c121',
+    Var('chromium_url') + '/chromium/tools/depot_tools.git' + '@' + 'dd2f620cce58bf627da3e3ec19eadedd71ab63b3',
   'v8/third_party/icu':
     Var('chromium_url') + '/chromium/deps/icu.git' + '@' + 'd7aff76cf6bb0fbef3afa6c07718f78a80a70f8f',
   'v8/third_party/instrumented_libraries':