[repo/Geneva] Prepare to .NET9

[Kielek]

Changes

Follow up #2251

Merge requirement checklist

• CONTRIBUTING guidelines followed (license requirements, nullable enabled, static analysis, etc.)
• [ ] Unit tests added/updated
• [ ] Appropriate CHANGELOG.md files updated for non-trivial changes
• [ ] Changes in public API reviewed (if applicable)

[codecov]

Codecov Report

Attention: Patch coverage is 70.23810% with 50 lines in your changes missing coverage. Please review.

Project coverage is 70.25%. Comparing base (71655ce) to head (a921fef).
Report is 610 commits behind head on main.

Files with missing lines	Patch %	Lines
...try.Exporter.Geneva/Internal/Tld/TldLogExporter.cs	17.24%	24 Missing ⚠️
...y.Exporter.Geneva/Internal/Tld/TldTraceExporter.cs	8.33%	11 Missing ⚠️
...eva/Metrics/OtlpProtobuf/OtlpProtobufSerializer.cs	72.22%	5 Missing ⚠️
...try.Exporter.Geneva/Internal/Tld/JsonSerializer.cs	75.00%	3 Missing ⚠️
...rter.Geneva/Internal/MsgPack/MsgPackLogExporter.cs	92.59%	2 Missing ⚠️
...r.Geneva/Internal/MsgPack/MessagePackSerializer.cs	80.00%	1 Missing ⚠️
...emetry.Exporter.Geneva/Internal/Tld/TldExporter.cs	0.00%	1 Missing ⚠️
...rter.Geneva/Internal/Tld/UncheckedASCIIEncoding.cs	50.00%	1 Missing ⚠️
...metry.Exporter.Geneva/Metrics/TlvMetricExporter.cs	83.33%	1 Missing ⚠️
...ransport/MetricWindowsEventTracingDataTransport.cs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2342      +/-   ##
==========================================
- Coverage   73.91%   70.25%   -3.66%     
==========================================
  Files         267      366      +99     
  Lines        9615    14097    +4482     
==========================================
+ Hits         7107     9904    +2797     
- Misses       2508     4193    +1685     

Flag	Coverage Δ
unittests-Contrib.Shared.Tests	84.04% <ø> (?)
unittests-Exporter.Geneva	53.16% <70.23%> (?)
unittests-Exporter.InfluxDB	95.14% <ø> (?)
unittests-Exporter.Instana	74.86% <ø> (?)
unittests-Exporter.OneCollector	94.51% <ø> (?)
unittests-Exporter.Stackdriver	79.26% <ø> (?)
unittests-Extensions	88.63% <ø> (?)
unittests-Extensions.Enrichment	100.00% <ø> (?)
unittests-Instrumentation.AWS	86.27% <ø> (?)
unittests-Instrumentation.AspNet	77.00% <ø> (?)
unittests-Instrumentation.AspNetCore	70.33% <ø> (?)
unittests-Instrumentation.ConfluentKafka	14.37% <ø> (?)
unittests-Instrumentation.ElasticsearchClient	80.12% <ø> (?)
unittests-Instrumentation.EntityFrameworkCore	57.06% <ø> (?)
unittests-Instrumentation.EventCounters	76.36% <ø> (?)
unittests-Instrumentation.GrpcCore	91.42% <ø> (?)
unittests-Instrumentation.GrpcNetClient	79.61% <ø> (?)
unittests-Instrumentation.Hangfire	93.58% <ø> (?)
unittests-Instrumentation.Http	74.11% <ø> (?)
unittests-Instrumentation.Owin	88.12% <ø> (?)
unittests-Instrumentation.Process	100.00% <ø> (?)
unittests-Instrumentation.Quartz	78.76% <ø> (?)
unittests-Instrumentation.Runtime	100.00% <ø> (?)
unittests-Instrumentation.SqlClient	89.77% <ø> (?)
unittests-Instrumentation.StackExchangeRedis	68.26% <ø> (?)
unittests-Instrumentation.Wcf	49.37% <ø> (?)
unittests-PersistentStorage	65.88% <ø> (?)
unittests-Resources.AWS	79.16% <ø> (?)
unittests-Resources.Azure	84.56% <ø> (?)
unittests-Resources.Container	67.34% <ø> (?)
unittests-Resources.Gcp	71.15% <ø> (?)
unittests-Resources.Host	72.56% <ø> (?)
unittests-Resources.OperatingSystem	76.98% <ø> (?)
unittests-Resources.Process	100.00% <ø> (?)
unittests-Resources.ProcessRuntime	78.26% <ø> (?)
unittests-Sampler.AWS	88.12% <ø> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...Telemetry.Exporter.Geneva/GenevaExporterOptions.cs	90.24% <100.00%> (+0.24%)	⬆️
...OpenTelemetry.Exporter.Geneva/GenevaLogExporter.cs	84.61% <100.00%> (+7.11%)	⬆️
...enTelemetry.Exporter.Geneva/GenevaTraceExporter.cs	82.05% <100.00%> (+7.05%)	⬆️
...xporter.Geneva/Internal/ConnectionStringBuilder.cs	95.12% <100.00%> (+2.18%)	⬆️
...xporter.Geneva/Internal/MsgPack/MsgPackExporter.cs	100.00% <100.00%> (ø)
...er.Geneva/Internal/MsgPack/MsgPackTraceExporter.cs	92.55% <100.00%> (ø)
...ry.Exporter.Geneva/Internal/TableNameSerializer.cs	98.90% <100.00%> (-0.04%)	⬇️
...ter.Geneva/Internal/Transports/EtwDataTransport.cs	85.00% <100.00%> (ø)
...eneva/Metrics/OtlpProtobuf/FieldNumberConstants.cs	20.00% <ø> (ø)
...a/Metrics/OtlpProtobuf/ProtobufSerializerHelper.cs	75.38% <100.00%> (ø)
... and 10 more

... and 375 files with indirect coverage changes

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