…rces-limits-requests

Automatic merge from submit-queue

Downward API proposal for resources (cpu, memory) limits and requests

Proposal to address #9473
This PR proposes three approaches to expose values of resource limits and requests as env vars and volumes.This proposal has details about merits and demerits of each approach, and I am looking for community feedback regarding which one (or may more than one) we would like to go with. Also would like to know if there is any other approach.

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