[Templates] Generate single test HTTPS Certificate

[javiercn]

• Generates a single HTTPS certificate for tests instead of one per test.

[amcasey]

Could we just check one in? I'm pretty sure the kestrel tests just have a folder of pre-made certs with various characteristics.

Edit: Oh, I see you're actually creating a real dev cert. Well, be careful about cert trust.

[javiercn]

/azp run aspnetcore-ci

[azure-pipelines]

Pipelines were unable to run due to time out waiting for the pull request to finish merging.

[javiercn]

Edit: Oh, I see you're actually creating a real dev cert. Well, be careful about cert trust.

These tests don't trust the cert in any way. They setup Selenium/Playwright/Dotnet to bypass the trust.