Added support for 10gb lambdas

[joswayski]

AWS now supports 10gb lambdas
https://aws.amazon.com/about-aws/whats-new/2020/12/aws-lambda-supports-10gb-memory-6-vcpu-cores-lambda-functions/

And in 1mb increments
https://aws.amazon.com/lambda/pricing/

So instead of checking whether the memory value is in one of the - allow options, we can just check if it is within the lambda memory range (128mb <--> 10240mb)

[eahefnawy]

Thanks @joswayski ... We'd love to have 10gb lambdas, but we'd just like to add it to the list of acceptable values.

[robertgoacher]

Is this change going to be implemented?