Use Jemalloc for better memory management

[ShanaLMoore]

Story

ref: https://github.com/scientist-softserv/nnp/pull/284/files#diff-dd2c0eb6ea5cfc6c4bd4eac30934e2d5746747af48fef6da689e85b752f39557R33

We noticed that Adventist prod ingest is going slower than expected. Rob recommended that we install jemalloc and then increase the scale of the workers if we are ingesting metadata only (which we are).

Acceptance Criteria

• [ ] Verify Jemalloc is installed.

Testing Instructions and Sample Files

• In the prod shell, a dev should be able to get an output when typing export | grep LD_PRELOAD

[ShanaLMoore]

Deployed to staging and verified the env var is set. Additionally discovered where I can change the concurrency of a pod on the fly. To change currency, visit the pod in rancher. Click on the three vertical dots and edit yaml. There is a variable called RAILS_MAX_THREADS. Change its value and click save.