Add Version func to otlpmetric and otlptrace

[remychantenay]

Towards #3946

Currently the SDK resources report the SDK version as the API version. If a project uses a different version of the SDK than the API this information will be incorrect. Add a version function to the SDK and use it.

Note: Part of the issue was fixed in #3949

PS: this is my very first contribution, please be gentle 🙏 😉

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: remychantenay / name: Remy Chantenay (fd015d8, 912a44f, abdf9d1, 0c438e0, 3615ee8)

[codecov]

Codecov Report

Merging #3956 (1809985) into main (1bc9b56) will decrease coverage by 0.1%.
The diff coverage is 100.0%.

Additional details and impacted files

@@           Coverage Diff           @@
##            main   #3956     +/-   ##
=======================================
- Coverage   82.0%   82.0%   -0.1%     
=======================================
  Files        171     174      +3     
  Lines      12969   12975      +6     
=======================================
+ Hits       10647   10651      +4     
- Misses      2102    2104      +2     
  Partials     220     220             

Impacted Files	Coverage Δ
sdk/resource/host_id.go	73.0% <ø> (ø)
exporters/otlp/otlpmetric/internal/header.go	100.0% <100.0%> (ø)
...xporters/otlp/otlpmetric/internal/oconf/options.go	79.8% <100.0%> (ø)
exporters/otlp/otlpmetric/otlpmetrichttp/client.go	76.6% <100.0%> (ø)
exporters/otlp/otlpmetric/version.go	100.0% <100.0%> (ø)
exporters/otlp/otlptrace/internal/header.go	100.0% <100.0%> (ø)
...ters/otlp/otlptrace/internal/otlpconfig/options.go	81.5% <100.0%> (ø)
exporters/otlp/otlptrace/otlptracehttp/client.go	77.5% <100.0%> (ø)
exporters/otlp/otlptrace/version.go	100.0% <100.0%> (ø)

... and 2 files with indirect coverage changes