Limit lambda memory to 2x-3x that observed used in logs

[dmannarino]

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Pull request type

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• Bugfix
• Feature
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• Refactoring (no functional changes, no api changes)
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• Other (please describe):
  Reduce costs by reducing the memory allocated for lambda use

What is the current behavior?

We over-provision the executor and postprocessor lambdas with ~3GB of memory

Issue Number: N/A

What is the new behavior?

The executor and postprocessor lambdas are only provisioned with ~2x the memory they have been observed using, saving costs.

Does this introduce a breaking change?

• Yes
• No

Other information