Disable NEW_RELIC_LICENSE_KEY env variable

[larivierec]

While this is offered as a feature, it essentially leaks the license key to environment variables when it's not managed by the initial cloudformation deployment.

We have many lambdas and reuse some of the license keys so not every stack can recreate the secret in a cross-account scenario.
You should allow us to be able to disable the templating of the environment variable NEW_RELIC_LICENSE_KEY completely.

I propose that a variable similar to the disableLicenseKeySecret is added to the options or a selfManagedSecret/selfManagedSSM is added in order to allow the license key not be leaked in the environment variables of the lambda function.

i'd be more than happy to propose a PR.

[workato-integration]

https://new-relic.atlassian.net/browse/NR-253911

[larivierec]

any update on this ticket?

[chaudharysaket]

Thank you for the suggestion. We will take this task in the coming week, due to some other tasks already planned ahead. In the meantime, if you get some time and want to assist with a proposed PR, we would welcome it. Thank you so much!