[infra] Update checked-in SDKs to 3.0.0-356.0.dev

Fixes: #51824
Change-Id: Icae09625b14ed3e574aa5f29caf9756e70390a2f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/290905
Commit-Queue: Alexander Thomas <[email protected]>
Reviewed-by: Jonas Termansen <[email protected]>

Author: athomas

DEPS

@@ -46,7 +46,7 @@ vars = {
   # Checked-in SDK version. The checked-in SDK is a Dart SDK distribution in a
   # cipd package used to run Dart scripts in the build and test infrastructure.
   # Contact dart-engprod@ if you need a checked-in SDK roll.
-  "sdk_tag": "version:3.0.0-322.0.dev",
+  "sdk_tag": "version:3.0.0-356.0.dev",
 
   # co19 is a cipd package. Use update.sh in tests/co19[_2] to update these
   # hashes.