Update metric sinks that could transmit enhanced tags

[bruceg]

The following sinks can emit metrics directly. They will all need to be audited to determine if they could emit enhanced tags (multi-valued or bare tags), and what work is required to complete that support. This task list will be edited to reflect the current status of this epic. This does not include sinks that can accept metrics via an encoding configuration.

• [x] #15522
• [x] #15523
• [X] #15831
• [x] #15641
• [x] #15524
• [x] #15607
• [x] #15619
• [x] #15812
• [x] #15834
• [x] #15832
• [x] #15581
• [x] #15582
• [x] #15525
• [x] #15621
• [x] #15640
• [X] vector @neuronull

[spencergilbert]

elasticsearch may be "done" already, as I think it calls into metric_to_log as it's way of handling metrics.

[bruceg]

I expect that most of these will require no further work. This is just a full list of everything that could be impacted, to track what still needs looking at. Once you do the investigation and determine it needs no further work, just check it off.

OTOH that reminds me that metric_to_log will also require an option to output single value tags as it does now or enhanced tags, which will then need to be exposed in the elasticsearch sink.