[otelecho] Use SpanStatusFromHTTPStatusCodeAndSpanKind on the middleware

[sgirones]

Fix the otelecho middleware and follow the OpenTelemetry specification.

For servers, 4XX status codes must not be treated as errors. OpenTelemetry's semconv package provides the SpanStatusFromHTTPStatusCodeAndSpanKind so the status code is treated different depending on whether the SpanKind is server or not

[linux-foundation-easycla]

The committers are authorized under a signed CLA.

• ✅ Salvador Girones Gil (8f6d390)

[pellared]

Hello @sgirones 👋
Are you able to sign the CLA so that we can accept your contribution?

[sgirones]

@pellared done!

[pellared]

I think it is worth adding an entry to CHANGELOG.md

[codecov]

Codecov Report

Merging #1848 (776e21c) into main (7b00c22) will not change coverage.
The diff coverage is 100.0%.

@@          Coverage Diff          @@
##            main   #1848   +/-   ##
=====================================
  Coverage   69.6%   69.6%           
=====================================
  Files        127     127           
  Lines       5391    5391           
=====================================
  Hits        3755    3755           
  Misses      1498    1498           
  Partials     138     138           

Impacted Files	Coverage Δ
...entation/github.com/labstack/echo/otelecho/echo.go	95.0% <100.0%> (ø)

[sgirones]

Thanks for the hand-holding @pellared. I added a changelog line.

Let me know if I there's anything missing I can help with.