test/aws_lambda_function: Fix failing tests related to 'runtime'
test/aws_lambda_function: Fix failing tests related to 'runtime'

Ninir/terraform-provider-aws,terraform-providers/terraform-provider-aws,Ninir/terraform-provider-aws,kjmkznr/terraform-provider-aws,kjmkznr/terraform-provider-aws,terraform-providers/terraform-provider-aws,nbaztec/terraform-provider-aws,Ninir/terraform-provider-aws,terraform-providers/terraform-provider-aws,kjmkznr/terraform-provider-aws,nbaztec/terraform-provider-aws,kjmkznr/terraform-provider-aws,terraform-providers/terraform-provider-aws,nbaztec/terraform-provider-aws,nbaztec/terraform-provider-aws,Ninir/terraform-provider-aws