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Cosmos trigger on Azure Functions v4 (.net 6) fails - cannot resolve SystemConfiguration.ConfigurationManager

See original GitHub issue

I have a Cosmos trigger on Azure Functions v4 which cannot register the function because of a failure to resolve System.Configuration.ConfigurationManager version 4.0.3.0 (aka 4.7.0)

Repro steps

Create a function project - .net6 preview, functions v4 - with the following function:

        [FunctionName("Function1")]
        public async Task Run([CosmosDBTrigger(
            databaseName: "Stats",
            containerName: "RawData",
            Connection = "DefaultConnection")]IReadOnlyList<object> input, ILogger log)
        {
            if (input != null && input.Count > 0)
            {
                log.LogInformation("Documents modified " + input.Count);
            }

            await Task.CompletedTask;
        }

local.settings.json is as follows:

{
    "IsEncrypted": false,
  "Values": {
    "AzureWebJobsStorage": "UseDevelopmentStorage=true",
    "FUNCTIONS_WORKER_RUNTIME": "dotnet",

    "DefaultConnection": "___REDACTED___"
  }
}

Expected behavior

Function should run …

Actual behavior

Microsoft.Azure.WebJobs.Host: Error indexing method 'Function1'. Microsoft.Azure.WebJobs.Extensions.CosmosDB: Cannot create container information for RawData in database Stats with lease leases in database Stats : Could not load file or assembly 'System.Configuration.ConfigurationManager, Version=4.0.3.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'. The system cannot find the file specified. Microsoft.Azure.Cosmos.Client: Could not load file or assembly 'System.Configuration.ConfigurationManager, Version=4.0.3.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'. The system cannot find the file specified.