Update V8 DEPS.

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/8c2d4f7..b03644a

TBR=machenbach@chromium.org,tmrts@chromium.org

Change-Id: I5f62d5448e47c9b05c9f6cb9e8dd8973d5ea77f5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2082005Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#66514}

DEPS

@@ -72,7 +72,7 @@ vars = {
 
 deps = {
   'v8/build':
-    Var('chromium_url') + '/chromium/src/build.git' + '@' + '8c2d4f7432eea81ff96dd8360abd20f004343a1f',
+    Var('chromium_url') + '/chromium/src/build.git' + '@' + 'b03644a571861d590327ab5a5be84a0cf7a4e176',
   'v8/third_party/depot_tools':
     Var('chromium_url') + '/chromium/tools/depot_tools.git' + '@' + '9ca9c52c4c04eee136f37bab1404ae0c2319bf06',
   'v8/third_party/icu':