AwsLambdaInstrumentor doesn't handle function exception, inconsistently flushes trace/metrics

[tammy-baylis-swi]

Describe your environment

• AWS Lambda
• Python 3.8
• Otel Python lambda layer built using opentelemetry-instrumentation-aws-lambda==0.44b0.dev (current main branch)
• Otel Collector layer

Steps to reproduce
I built an Otel Python lambda layer using contents of this repo's main branch. I equipped an AWS Lambda function with this layer, then I invoked to immediately raise Exception. A local instance of Otel Collector exporting to console/logging/debug received traces from the function sometimes and never received some custom metrics.

What is the expected behavior?
All traces and any custom metrics should be generated and exported, even if lambda function raises exception.

Some of the other instrumentors handle exceptions and adjust + still report telemetry. For example: requests, asgi (via try-except to set attributes and finally to export telemetry).

What is the actual behavior?
Some traces and no custom metrics are exported when lambda function raises exception.

Additional context

[tammy-baylis-swi]

Please may I be assigned to this. I'm working on a fix in #2245.