Remove net452 and net46 from the in-memory exporter project

[joaopgrassi]

Another project from #2138

• CHANGELOG.md updated for non-trivial changes
• Design discussion issue #
• Changes in public API reviewed

[CodeBlanch]

LGTM

[codecov]

Codecov Report

Merging #2144 (e6a98be) into main (17ed3f3) will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #2144      +/-   ##
==========================================
- Coverage   85.00%   84.99%   -0.02%     
==========================================
  Files         187      187              
  Lines        6124     6124              
==========================================
- Hits         5206     5205       -1     
- Misses        918      919       +1     

Impacted Files	Coverage Δ
...rter.InMemory/InMemoryExporterLoggingExtensions.cs	0.00% <ø> (ø)
...emetry.Api/Internal/OpenTelemetryApiEventSource.cs	79.41% <0.00%> (-2.95%)	⬇️

[reyang]

LGTM.

[joaopgrassi]

I missed the OpenTelemetry.Tests using the InMemory project.. as these don't run on Linux :(. I guess we can leave this and merge once that one is also changed to remove these targets?

[cijothomas]

I missed the OpenTelemetry.Tests using the InMemory project.. as these don't run on Linux :(. I guess we can leave this and merge once that one is also changed to remove these targets?

You can remove net452 and net46 from OpenTelemetry.Tests and instead add net461

[joaopgrassi]

You can remove net452 and net46 from OpenTelemetry.Tests and instead add net461

Yep, done!

[cijothomas]

we'll get rid of netcore2.1 soon, so this'd be lot more simpler.! (2.1 is EOL next month!) We can start removing as soon as the current wave of .netframework removals.