[infra] Upgrade Win to 2019

Change-Id: I7994b1e67f433b61159bd4107bee8cd86e6eb68f
Reviewed-on: https://skia-review.googlesource.com/c/skcms/+/261980
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
Reviewed-by: Ravi Mistry <rmistry@google.com>
diff --git a/infra/bots/tasks.json b/infra/bots/tasks.json
index 53f4781..88cbea4 100644
--- a/infra/bots/tasks.json
+++ b/infra/bots/tasks.json
@@ -147,7 +147,7 @@
         "clang_win"
       ],
       "dimensions": [
-        "os:Windows-Server-14393",
+        "os:Windows-Server-17763",
         "gpu:none",
         "pool:Skia"
       ],