fix(assuredworkloads): reenable on windows

[dbolduc]

Probably fixes #8198

We require protobuf >=21.1, which handles STATUS_PENDING: https://github.com/protocolbuffers/protobuf/blob/7062d0a2d0075d5e7d5c294fd3984df67a976da3/src/google/protobuf/port_def.inc#L848-L849

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This change is 

[google-cloud-cpp-bot]

Google Cloud Build Logs
For commit: 1461973809fc654627f8d076963b8994d2e750ac

• Public Access Build Logs
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• Kokoro Logs (requires auth)

ℹ️ NOTE: Kokoro logs are linked from "Details" below.

[codecov]

Codecov Report

Merging #9467 (1461973) into main (78e6c18) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #9467   +/-   ##
=======================================
  Coverage   94.64%   94.64%           
=======================================
  Files        1485     1485           
  Lines      136689   136689           
=======================================
+ Hits       129364   129368    +4     
+ Misses       7325     7321    -4     

Impacted Files	Coverage Δ
...bigtable/examples/bigtable_hello_instance_admin.cc	80.00% <0.00%> (-2.00%)	⬇️
...le/cloud/storage/internal/curl_download_request.cc	88.59% <0.00%> (+1.00%)	⬆️
google/cloud/pubsub/subscriber_connection_test.cc	98.31% <0.00%> (+1.12%)	⬆️
...e/cloud/pubsublite/internal/alarm_registry_impl.cc	100.00% <0.00%> (+2.94%)	⬆️

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[dbolduc]

Result of manually triggering cmake-release: https://source.cloud.google.com/results/invocations/9834453e-d4db-467f-963f-83336cf490ad

[dbolduc]

Merging, and if the CI breaks, I will accept the consequences.