fix(template-render-server): ensure sequential execution in render queue

Fix the Promise chain in queueRender function to properly wait for each 
processRender task to complete before starting the next one. This prevents 
potential concurrent execution of render jobs that could lead to resource 
contention and unexpected behavior.

The fix changes the callback from:
queue.then(() => { processRender(jobId); })
to:
queue.then(() => processRender(jobId))

This ensures the Promise returned by processRender is properly integrated 
into the Promise chain.