feat(httpd): Add option to authenticate debug/pprof and ping endpoints

[gunnaraasen]

Fixes #10167

Adds pprof-auth-enabled and ping-auth-enabled configuration options which can enable authentication on all /debug and /ping endpoints. This also covers the prometheus /metrics and deprecated /status endpoints.

With these additions, all InfluxDB endpoints will require authentication with the following configuration:

[http]
  auth-enabled = true
  pprof-auth-enabled = true
  ping-auth-enabled = true

Note that go tool pprof does not support authentication so it will not work when pprof-auth-enabled is enabled.

• CHANGELOG.md updated with a link to the PR (not the Issue)
• Well-formatted commit messages
• Rebased/mergeable
• Tests pass
• Documentation updated or issue created (provide link to issue/pr)
• Signed CLA (if not already signed)

[gunnaraasen]

I've updated the example config with a note about the auth-enabled and pprof-enabled dependent settings. Will merge once tests pass.

[jacobmarble]

If someone needs a profile from an OSS instance with pprof auth enabled, I guess they grab it with curl (or whatever) instead of the `go` CLI?

[gunnaraasen]

Yup, a profile would need to be pulled with curl, for example:

curl -o profiles.tar.gz -u username:password "http://localhost:8086/debug/pprof/all?cpu=true"

[dontsovcmc]

Wow! I think, that there is an error, but found that init-influxdb.sh doesn’t work without -e INFLUXDB_HTTP_AUTH_ENABLED=true
influxdata/influxdata-docker#281 (comment)