Additional fix for #1160 when running Java lambdas locally

[krrg]

#1160 describes problems caused by AWS SDK classes from the localstack-utils-fat.jar overriding classes defined in the actual Lambda jar/zip itself. This causes numerous incompatibility problems.

I was able to isolate and repro this problem with a minimal example ( https://github.com/krrg/localstack-java-classpath-debug )

@whummer implemented a partial fix for this that moved the localstack-utils-fat.jar later on the classpath, but this fix only applied to lambdas being run using the docker executor.

This PR takes a similar approach, but this time for lambdas being executed locally. Using the minimal example above, I verified that the classpath is now correctly ordered for local lambdas and that my example is able to be invoked without error.

[coveralls]

Coverage decreased (-0.07%) to 72.91% when pulling 8ce6923 on krrg:master into a0fadac on localstack:master.

[whummer]

Good catch - thanks for providing this fix @krrg ! 👍