Set build environment type as new arg

When building a conda environment in the Dockerfile I am getting the following error message:

```
CondaMemoryError: The conda process ran out of memory. Increase system memory and/or try again.
```

Would it be possible to have an argument to set the build environment type as described [here](https://docs.aws.amazon.com/codebuild/latest/userguide/build-env-ref-compute-types.html) ?