[wasm][xharness] install development SSL certificate on Helix agent before xharness run

[pavelsavara]

I added HTTPS listener to existing kestrel server in the xharness last week.
After the change propagated to this repo, I can see following issue on Helix

crit: System.InvalidOperationException: Unable to configure HTTPS endpoint. 
No server certificate was specified, and the default developer certificate could not be found or is out of date. 
To generate a developer certificate run 'dotnet dev-certs https'.

[ghost]

Tagging subscribers to this area: @Anipik, @safern, @ViktorHofer
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Issue Details

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I added HTTPS listener to existing kestrel server in the xharness last week.
After the change propagated to this repo, I can see following issue on Helix

crit: System.InvalidOperationException: Unable to configure HTTPS endpoint. 
No server certificate was specified, and the default developer certificate could not be found or is out of date. 
To generate a developer certificate run 'dotnet dev-certs https'.

Author:	pavelsavara
Assignees:	-
Labels:	area-Infrastructure-libraries
Milestone:	-

[ViktorHofer]

Should this issue already be resolved? I'm stilling hitting it in CI:

Connection refused [::ffff:127.0.0.1]:39621 (localhost:39621)
[09:28:01] crit: System.InvalidOperationException: Unable to configure HTTPS endpoint. No server certificate was specified, and the default developer certificate could not be found or is out of date.
                 To generate a developer certificate run 'dotnet dev-certs https'. To trust the certificate (Windows and macOS only) run 'dotnet dev-certs https --trust'.
                 For more information on configuring HTTPS see https://go.microsoft.com/fwlink/?linkid=848054.

Log: https://helixre8s23ayyeko0k025g8.blob.core.windows.net/dotnet-runtime-refs-pull-53244-merge-70825d7803a14d418d/System.Runtime.Handles.Tests/console.0a5ec6f2.log?sv=2019-07-07&se=2021-06-15T09%3A21%3A11Z&sr=c&sp=rl&sig=e7vhUZhAD5az%2F02xFlxyPLPGrevU2QGJehJHI4SQh9I%3D

Build: https://dev.azure.com/dnceng/public/_build/results?buildId=1156998&view=ms.vss-test-web.build-test-results-tab&runId=34940296&resultId=168965&paneView=dotnet-dnceng.dnceng-build-release-tasks.helix-test-information-tab

[premun]

I know about this fix: 57bdb95

[pavelsavara]

Looking at Viktor's log I can see that the poweshell way of cert installation is there.
But it failed with execute.sh: powershell: not found which I have not noticed.