How to increase dgraph lambda max memory limit?

I’m fetching some information and I want to insert them into the database using a Lambda Server(using docker localy).
The problem is that it uses 70MB of memory and Dgraph Lambda PM2 restarts the process each time I call this service:

2021-12-25T08:41:17: PM2 log: pid=52 msg=process killed
2021-12-25T13:47:39: PM2 log: [PM2][WORKER] Process 1 restarted because it exceeds --max-memory-restart value (current_memory=72474624 max_memory_limit=67108864 [octets])
2021-12-25T13:47:39: PM2 log: App [dgraph-lambda:1] starting in -cluster mode-
2021-12-25T13:47:39: PM2 log: App [dgraph-lambda:1] online
Server Listening on port 8686!

I took a look at the source and apparently this limit is hard coded here:

Also found another pull request that was because of a similar issue:
https://github.com/dgraph-io/dgraph-lambda/pull/4

Shouldn’t max_memory_limit be an environment variable that people can set their desired memory limit?

I created this PR. I think it will solve the issue both for max memory limit and the number of PM2 instances. Also checked it by building the docker image locally.

Can anyone review this?

The PR looks good. Thanks, @pshaddel!