Support PollingOverWebSocket for net60 Services

[nathanwoctopusdeploy]

Background

This PR adds support for WebSocket Services on net60. This will allow net60 Tentacles on Windows and Linux to support PollingOverWebSockets

This does not change the Client requirements e.g. Octopus Server, which must still be run on Windows (net48 or net60) as HttpListener doesn't support SSL binding in net60 on Linux

Results

Before

PollingOverWebSocket Services (Tentacles) had to be run on Windows under net48

After

PollingOverWebSocket Services (Tentacles) can be run on Windows under net48 and net60 and on Linux under net60

How to review this PR

Quality :heavy_check_mark:

Pre-requisites

• [ ] I have read How we use GitHub Issues for help deciding when and where it's appropriate to make an issue.
• [ ] I have considered informing or consulting the right people, according to the ownership map.
• [ ] I have considered appropriate testing for my change.

[nathanwoctopusdeploy]

[sc-53419]

[shortcut-integration[bot]]

This pull request has been linked to Shortcut Story #53419: Enable WebSocket support on net60 to increase test coverage (just not Linux).