fix: ensure ingress-nginx uses the incoming X-Forwarded-For header

Description

Currently, ingress-nginx does not forward the X-Forwarded-For header from the incoming request. Instead, it passes the IP it itself sees to X-Forwarded-For and sends the original values to X-Original-Forwarded-For.

This creates an issue when we are trying to deal with rate limits in Open edX or perhaps just want to use the full IP stack for analytics. In this MR, we are adding the compute-full-forwarded-for config, which along with the existing use-forwarded-headers makes sure ingress-nginx retains the original values of X-Forwarded-For header and only appends to it.

Doing this is safe as Open edX has in-built checks which ensure that only the right-most IP from X-Forwarded-For is used which would remain unaffected by this change. Also, X-Original-Forwarded-For header is still passed despite this change, which means the "untrusted" IPs can still be identified if so required.

Supporting information

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Testing instructions

Steps to test the changes:

1. TBD

Dependencies

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Screenshots

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Checklist

If any of the items below is not applicable, do not remove them, but put a check in it.

• All providers include the new feature/change
• All affected providers can provision new clusters
• Unit tests are added/updated
• Documentation is added/updated
• The TOOLS_CONTAINER_IMAGE_VERSION in ci_vars.yml is updated
• The grove-template repository is updated

Additional context

BB-8358