Update google_benchmark

Rolling v8/third_party/google_benchmark/src: https://chromium.googlesource.com/external/github.com/google/benchmark/+log/5704cd4..a480a08

[nfc] Reformat doc-string in generate_export_header (#1376) (Vy Nguyen)
https://chromium.googlesource.com/external/github.com/google/benchmark/+/a480a08

Fix Bazel build breakage caused by commit 6a894bd. (#1374) (Paul Wankadia)
https://chromium.googlesource.com/external/github.com/google/benchmark/+/808571a

Build `//:benchmark` as a static library only. (#1373) (Paul Wankadia)
https://chromium.googlesource.com/external/github.com/google/benchmark/+/6a894bd

R=v8-waterfall-sheriff@grotations.appspotmail.com,mtv-sf-v8-sheriff@grotations.appspotmail.com,mlippautz@chromium.org

Change-Id: Ic2015e271f35597f3b78de84fbe88e5ae1f02d79
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3534848
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Bot-Commit: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#79521}

DEPS

@@ -221,7 +221,7 @@ deps = {
     'condition': 'checkout_fuchsia',
   },
   'third_party/google_benchmark/src': {
-    'url': Var('chromium_url') + '/external/github.com/google/benchmark.git' + '@' + '5704cd4c8cea889d68f9ae29ca5aaee97ef91816',
+    'url': Var('chromium_url') + '/external/github.com/google/benchmark.git' + '@' + 'a480a088fe647eb829ead0d0bbbd5821b2cc8b85',
   },
   'third_party/googletest/src':
     Var('chromium_url') + '/external/github.com/google/googletest.git' + '@' + 'b007c54f2944e193ac44fba1bc997cb65826a0b9',