log level param not effective on the Gloo pod

[bcollard]

Describe the bug
Changing the log level of the Gloo pod is not effective.
It's possible to change the log level itself, using the new Helm charts options or the REST API (curl -X GET localhost:9091/logging), but in fact, it won't affect logs output.

To Reproduce
Steps to reproduce the behavior:

kubectl -n gloo-system port-forward deploy/gloo 9091 &
curl -X PUT localhost:9091/logging -d '{"level":"error"}'

1. kube apply a modified VS
2. kubectl logs the gloo pod
3. See logs like with info level:

{"level":"info","ts":"2021-04-23T13:51:41.705Z","logger":"proxy-validator","caller":"validation/server.go:170","msg":"received proxy validation request"}
{"level":"info","ts":"2021-04-23T13:51:41.706Z","logger":"proxy-validator.translator","caller":"translator/translator.go:167","msg":"computing envoy resources for listener: listener-::-8080"}
{"level":"info","ts":"2021-04-23T13:51:41.707Z","logger":"proxy-validator.translator","caller":"translator/translator.go:167","msg":"computing envoy resources for listener: listener-::-8443"}
{"level":"info","ts":"2021-04-23T13:51:41.708Z","logger":"proxy-validator","caller":"validation/server.go:176","msg":"proxy validation report result: listener_reports:{http_listener_report:{virtual_host_reports:{route_reports:{}}}}  listener_reports:{http_listener_report:{}}"}
{"level":"info","ts":"2021-04-23T13:51:42.068Z","logger":"proxy-validator","caller":"validation/server.go:170","msg":"received proxy validation request"}
{"level":"info","ts":"2021-04-23T13:51:42.069Z","logger":"proxy-validator.translator","caller":"translator/translator.go:167","msg":"computing envoy resources for listener: listener-::-8080"}
{"level":"info","ts":"2021-04-23T13:51:42.070Z","logger":"proxy-validator.translator","caller":"translator/translator.go:167","msg":"computing envoy resources for listener: listener-::-8443"}
{"level":"info","ts":"2021-04-23T13:51:42.072Z","logger":"proxy-validator","caller":"validation/server.go:176","msg":"proxy validation report result: listener_reports:{http_listener_report:{virtual_host_reports:{route_reports:{}}}}  listener_reports:{http_listener_report:{}}"}
{"level":"info","ts":"2021-04-23T13:51:42.649Z","logger":"gloo-ee.v1.event_loop.setup.v1.event_loop.envoyTranslatorSyncer","caller":"syncer/envoy_translator_syncer.go:78","msg":"begin sync 14483205116457499483 (1 proxies, 37 upstreams, 40 endpoints, 1 secrets, 21 artifacts, 0 auth configs, 0 rate limit configs)","version":"1.7.2"}
{"level":"info","ts":"2021-04-23T13:51:42.650Z","logger":"gloo-ee.v1.event_loop.setup.v1.event_loop.envoyTranslatorSyncer.translator","caller":"translator/translator.go:167","msg":"computing envoy resources for listener: listener-::-8080","version":"1.7.2"}
{"level":"info","ts":"2021-04-23T13:51:42.650Z","logger":"gloo-ee.v1.event_loop.setup.v1.event_loop.envoyTranslatorSyncer.translator","caller":"translator/translator.go:167","msg":"computing envoy resources for listener: listener-::-8443","version":"1.7.2"}
{"level":"info","ts":"2021-04-23T13:51:42.652Z","caller":"cache/simple.go:140","msg":"respond open watch 9[listener-::-8080-routes] with new version \"15269475656591533752\""}
{"level":"info","ts":"2021-04-23T13:51:42.652Z","logger":"gloo-ee.v1.event_loop.setup.v1.event_loop.envoyTranslatorSyncer","caller":"syncer/envoy_translator_syncer.go:173","msg":"Setting xDS Snapshot","version":"1.7.2","key":"gloo-system~gateway-proxy","clusters":36,"listeners":1,"routes":1,"endpoints":36}
{"level":"info","ts":"2021-04-23T13:51:42.652Z","logger":"gloo-ee.v1.event_loop.setup.v1.event_loop.envoyTranslatorSyncer","caller":"syncer/envoy_translator_syncer.go:184","msg":"end sync 14483205116457499483","version":"1.7.2"}

Additional context
Add any other context about the problem here, e.g.

• Gloo Edge version v1.7.0, 1.7.1, 1.7.2
• Kubernetes version KinD 1.20