Semantic Convention generation tooling

[Aneurysm9]

This adds a tool to use the otel/semconvgen container image to generate resource and trace semantic conventions from the specification. It is not yet integrated with build processes and must be manually run, but it can produce constant and variable declarations with reasonable godoc.

Fixes #1879.

[MadVikingGod]

Just because I couldn't tell I created a gist of the differences between keys: https://gist.github.com/MadVikingGod/9d108870779419171e7edecafe86e323

This isn't a comment on if this is appropriate or not, just so others don't have to try and work this out.

It looks like a few new Keys:

• AWS*
• DBCassandra
• FaaS*
• MessagingKafka*
• other misc keys

Major change of

• K8s* to K8S*
• CodeLineNumberKey to CodeLinenoKey
• DBRedisDBIndexKey to DBRedisDatabaseIndexKey

And the removal of

• RPCMessage*
• MessagingRabbit
• RPCNameKey

[Aneurysm9]

Thanks for doing that analysis @MadVikingGod! I've added replacements to fix the K8S* (though I wonder whether that's right), Redis, and LineNumber key names.

There were some FaaS* keys previously, though I think they were primarily in resource.go and new ones were added in trace.go. All of the added and removed keys are according to the conventions as they currently exist in the specification repo. If we want to restore the removed keys we'll need to get them into the spec and re-generate these files.

[XSAM]

👍🏼

[pellared]

Looks nice 👍 Added a just few comments

[MadVikingGod]

Other than finding the repo root magic, I think this is GTG.

[MadVikingGod]

Is this just moved out of the other files? It doesn't seem like this was generated like the other files.

[Aneurysm9]

This was just moved out of the other files. It doesn't exist in the conventions and I'm not actually sure we should be introducing it, but it was used in some of the helpers here and I figured it was easier to move closer to its use and we can discuss whether to actually keep them separately if needed.

[codecov]

Codecov Report

Merging #1891 (1432e46) into main (6219221) will increase coverage by 0.0%.
The diff coverage is n/a.

@@          Coverage Diff          @@
##            main   #1891   +/-   ##
=====================================
  Coverage   79.3%   79.3%           
=====================================
  Files        139     139           
  Lines       7425    7425           
=====================================
+ Hits        5892    5894    +2     
+ Misses      1286    1285    -1     
+ Partials     247     246    -1     

Impacted Files	Coverage Δ
semconv/http.go	95.2% <ø> (ø)
sdk/trace/batch_span_processor.go	87.1% <0.0%> (+1.5%)	⬆️