Update wasm-spec.

Rolling v8/test/wasm-js/data: https://chromium.googlesource.com/external/github.com/WebAssembly/spec/+log/7940fa4..b568df7

[test] More inconsistent lengths (#1029) (Wanming Lin)
https://chromium.googlesource.com/external/github.com/WebAssembly/spec/+/b568df7

[interpreter] Fix broken link (#1035) (Rikard Hjort)
https://chromium.googlesource.com/external/github.com/WebAssembly/spec/+/8c8f5f1

TBR=ahaas@chromium.org,clemensh@chromium.org

Change-Id: I66b322850497c17474a179c793e3aa834e2df1d3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1668769Reviewed-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@{#62300}

DEPS

@@ -236,7 +236,7 @@ deps = {
     'dep_type': 'cipd',
   },
   'v8/test/wasm-js/data':
-    Var('chromium_url') + '/external/github.com/WebAssembly/spec.git' + '@' + '7940fa456c6a9243a29dc7da67fe54c01f67a0ca',
+    Var('chromium_url') + '/external/github.com/WebAssembly/spec.git' + '@' + 'b568df78595ea6d6c6c6f6d6b931674900dd3f1d',
   'v8/third_party/perfetto':
     Var('android_url') + '/platform/external/perfetto.git' + '@' + '10c98fe0cfae669f71610d97e9da94260a6da173',
   'v8/third_party/protobuf':