[SourceGen] Bug fix for scenarios with $return output binding

[satvu]

Issue describing the changes in this PR

resolves #2073

Pull request checklist

• My changes do not require documentation changes
  • Otherwise: Documentation issue linked to PR
• My changes should not be added to the release notes for the next release
  • Otherwise: I've added my notes to release_notes.md
• My changes do not need to be backported to a previous version
  • Otherwise: Backport tracked by issue/PR #issue_or_pr
• I have added all required tests (Unit tests, E2E tests)

Additional information

For HttpTrigger functions with a method attribute output binding, we need to drop the http-related output binding. Example of legacy metadata:

[
  {
    "name": "Function1",
    "scriptFile": "FunctionApp154.dll",
    "entryPoint": "FunctionApp154.Function1.Run",
    "language": "dotnet-isolated",
    "properties": {
      "IsCodeless": false
    },
    "bindings": [
      {
        "name": "req",
        "direction": "In",
        "type": "httpTrigger",
        "authLevel": "Function",
        "methods": [
          "get",
          "post"
        ],
        "properties": {}
      },
      {
        "name": "$return",
        "direction": "Out",
        "type": "queue",
        "queueName": "myqueue",
        "connection": "Con",
        "properties": {}
      }
    ]
  }
]

Another case added to the tests is an HttpTrigger function with a custom return type that does not include a property of the type HttpRequestData. In this case, the http-related output binding is also dropped.