Feature Request

What problem are you trying to solve?

Currently, Linkerd proxy provides LINKERD2_PROXY_DNS_CANONICALIZE_TIMEOUT environment variable that allows the default 100ms timeout to be overridden. linkerd/linkerd2-proxy#175
However there is no proxy configuration or annotation to override this environment value during helm or customized installation or even using release pipeline

How should the problem be solved?

we should probably provide linkerd config annotation that can override environment variables like LINKERD2_PROXY_DNS_CANONICALIZE_TIMEOUT

config.linkerd.io/proxy-dns-canonicalize-timeout : "200"

Any alternatives you've considered?

Alternatively we should consider providing CLI flag too --proxy-dns-canonicalize-timeout

How would users interact with this feature?

For example, we can add annotation to our proxy config,

             annotations:
                   config.linkerd.io/proxy-dns-canonicalize-timeout : "200"

or can also be done manually using linkerd CLI
kubectl get deployment ... | linkerd inject --proxy-dns-canonicalize-timeout : "200" | kubectl apply -