[tz] Roll ICU to d3c1cdc3 for tz2020c

https://chromium.googlesource.com/chromium/deps/icu.git/+log/715ec351..d3c1cdc3

d3c1cdc Update IANA timezone db to 2020c

TBR=jshin@chromium.org

Bug: 1141065
Change-Id: I8ab1d6066c80202517fe1fe04a6c93d80f66bc16
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2494029Reviewed-by: Frank Tang <ftang@chromium.org>
Commit-Queue: Frank Tang <ftang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#820996}

DEPS

@@ -1043,7 +1043,7 @@ deps = {
     Var('chromium_git') + '/chromium/deps/hunspell_dictionaries.git' + '@' + '18e09b9197a3b1d771c077c530d1a4ebad04c167',
 
   'src/third_party/icu':
-    Var('chromium_git') + '/chromium/deps/icu.git' + '@' + '715ec351c0bcdd6b2d22f36e7d33b8e2ec519846',
+    Var('chromium_git') + '/chromium/deps/icu.git' + '@' + 'd3c1cdc3fa0f1768ecd76ac5315a9bcf4114a087',
 
   'src/third_party/icu4j': {
       'packages': [