Expose FirstRunID in WorkflowExecutionInfo under DescribeWorkflowExecutionResponse

[dhiaayachi]

Is your feature request related to a problem? Please describe.
I need to workaround with issue that runId is not stable after continueAsNew or reset.
It's available in https://github.com/temporalio/sdk-go/blob/1f0296cdf9d7655269beed439ad1769dd8040654/internal/workflow.go#L1072 but I also need it from describeWF API

Describe the solution you'd like
Add it in the api and then server

Describe alternatives you've considered
No easy alternative currently (unless I redesign and rebuild the system:( )

Additional context
More context of my current workflows running in production (needed in indeedeng/iwf#404 )
When workflowA is running, it may kickoff a workflowA1 as a child workflow and then waiting for external to signal A1.
A1 is currently based on A's workflowID+"number suffix".
However, this is not sufficient when workflowA us using IdReusePolicy to reuse the workflowID.

This could be fixed if we can use firstRunId instead. Using currentRunID will not work because of continueAsNew and reset.

[dhiaayachi]

Thanks for reporting this issue.
This is a known issue in Temporal's SDK and you can find more details in this Github Issue.
This will be resolved once this issue is fixed.