Fix dev-certs EventSource Boolean payload

[HengYpinn]

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Fix the dev-certs EventSource Boolean payload

Description

CertificateManagerEventSource.ExportCertificateStart declares includePrivateKey as a Boolean, but passed "with" or "without" to WriteEvent. EventSource consumers therefore received a string payload that did not match the event contract.

This change writes the Boolean value directly, updates the event message to format that value, and adds regression coverage for both true and false payloads.

Testing

.\.dotnet\dotnet.exe test .\src\Shared\test\Shared.Tests\Microsoft.AspNetCore.Shared.Tests.csproj --no-build --no-restore --verbosity minimal

Passed: 1,329; Failed: 0; Skipped: 0.

Fixes #29541

[dotnet-policy-service]

Thanks for your PR, @HengYpinn. Someone from the team will get assigned to your PR shortly and we'll get it reviewed.

[Copilot]

Pull request overview

Fixes an EventSource contract mismatch in CertificateManagerEventSource.ExportCertificateStart where a bool parameter was emitted as a string payload, ensuring consumers receive the expected Boolean value.

Changes:

• Update ExportCertificateStart to write the includePrivateKey Boolean directly to WriteEvent.
• Adjust the event message format to reflect the Boolean payload.
• Add regression tests validating the payload type/value for both true and false.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/Shared/CertificateGeneration/CertificateManager.cs	Corrects EventSource payload type for ExportCertificateStart and updates the message format accordingly.
src/Shared/test/Shared.Tests/CertificateManagerEventSourceTests.cs	Adds regression coverage to validate the event payload includes a Boolean for includePrivateKey and isolates tests via a non-parallelized collection.

[HengYpinn]

@dotnet-policy-service agree