[BUG]: http headers are lowercase

[cveld]

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Extension name

ServerTaskHelper\AzureFunctionBasicHandler\AzureFunctionBasicHandler.csproj

Extension version

N/A

Issue Description

Either Azure DevOps or the dotnet middleware is converting the headers to lowercase which actually is a good thing as this is desired by the http spec.

But the dotnet code does not expect this to happen and errors out:

System.Private.CoreLib: Exception while executing function: MyBasicFunction. DistributedTask.ServerTask.Remote.Common: Required properties 'ProjectId, PlanId, PlanUrl, JobId, TimelineId, AuthToken' are missing. Please provide these values and try again.

Environment type (Please select at least one enviroment where you face this issue)

• Self-Hosted
• Microsoft Hosted
• VMSS Pool
• Container

Azure DevOps Server type

dev.azure.com (formerly visualstudio.com)

Azure DevOps Server Version (if applicable)

No response

Operation system

N/A

Relevant log output

N/A

Full task logs with system.debug enabled

N/A

Repro steps

N/A