daemon/logger/awslogs: avoid user-agent test race - #53438

• Fixes: Flaky test: TestNewAWSLogsClientUserAgentHandler (race: concurrent map read and map write) #53273

Summary

Make the AWS logs user-agent unit test inspect the SDK-built request through an injected synchronous HTTP client.

The real net/http transport serializes request headers on a separate goroutine, which can race with AWS middleware header mutation — the failure seen on Windows in TestNewAWSLogsClientUserAgentHandler, where net/http.(*persistConn).writeLoop was reading the request header map in Header.sortedKeyValues while the middleware wrote to it.

The test only needs to verify the final User-Agent header, so replacing the httptest.Server with config.WithHTTPClient and a smithyhttp.ClientDoFunc inspects the actual SDK-built request synchronously and avoids the transport concurrency entirely. The AWS middleware path under test is unchanged.

Scope

One test file changes. No production code or behavior is touched.

Testing

• go test -race -run '^TestNewAWSLogsClientUserAgentHandler$' -count=100 ./daemon/logger/awslogs — ok
• go test -race ./daemon/logger/awslogs — ok
• GOOS=windows GOARCH=amd64 go test -c ./daemon/logger/awslogs — ok
• git diff --check — clean

Risks

The revised test no longer exercises Go's real HTTP transport. That transport is outside the behavior under test; the AWS middleware still builds the actual request that the injected client inspects.

Created with: Codex