Propagate locateFunction errors in AWS Lambda custom runtime

[mrjv]

Is your feature request related to a problem? Please describe.
If locating a function fails in the AWS Lambda custom runtime, the Lambda times out instead of propagating the error. Errors in the following method call are currently not propagated to the Lambda Error API endpoint:

spring-cloud-function/spring-cloud-function-adapters/spring-cloud-function-adapter-aws/src/main/java/org/springframework/cloud/function/adapter/aws/CustomRuntimeEventLoop.java

Line 138 in 49c1686

FunctionInvocationWrapper function = locateFunction(environment, functionCatalog, response.getHeaders());

Describe the solution you'd like
Catch exceptions thrown by CustomRuntimeEventLoop#locateFunction and post them to the Lambda error endpoint (/runtime/invocation/AwsRequestId/error). This is already handled for function invocations (#841).

In general it would be good to propagate as many errors as possible inside the CustomRuntimeEventLoop loop to avoid Lambda timeouts.