Accept 503 responses from PE /status APIs

[Sharpie]

The puppetlabs/trapperkeeper-status library that provides the
/status/v1 API of various PE services will respond with a
HTTP 503 status code if any sub-service is not in a healthy state.
By default, Telegraf HTTP inputs will only accept 200 as a
successful response code. This state of affairs leads to situations
like an outage in pe-orchestration-services resulting in Telegraf
rejecting perfectly good JRuby metrics from pe-puppetserver on
compilers because the pcp-broker sub-service is unhealthy.

This commit updates the Telegraf configuration to accept HTTP 503
as a successful return code in addition to 200 so that an attempt
is made to process and store metrics data during outages of external
services.

[puppet-community-rangefinder]

puppet_metrics_dashboard::profile::compiler is a type

that may have no external impact to Forge modules.

puppet_metrics_dashboard::profile::puppetdb is a type

that may have no external impact to Forge modules.

This module is declared in 0 of 578 indexed public Puppetfiles.

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These results were generated with Rangefinder, a tool that helps predict the downstream impact of breaking changes to elements used in Puppet modules. You can run this on the command line to get a full report.

Exact matches are those that we can positively identify via namespace and the declaring modules' metadata. Non-namespaced items, such as Puppet 3.x functions, will always be reported as near matches only.

[jarretlavallee]

Good call.