Add 'Client Reports' to the .NET SDK

[bruno-garcia]

Sentry's protocol now offers a way to report counts and reason to why data gets dropped.

Spec: https://develop.sentry.dev/sdk/client-reports/

This was implemented in other places that can be used as a reference:

• JavaScript: feat(browser): Client Report Support  sentry-javascript#3955
• Python: feat(transport): Client Report Support sentry-python#1181
• Relay: feat(client-reports): Protocol support for client reports  relay#1074

This will also be implemented in the following SDKs so collaborating with folks adding support there is ideal

• Dart: Add 'Client Reports' to the Dart SDK sentry-dart#735
• Java: Add 'Client Reports' to the Java and Android SDKs sentry-java#1894
• Apple: Add 'Client Reports' to the Apple SDK sentry-cocoa#1655
• React Native: Add 'Client Reports' to the React Native SDK sentry-react-native#2034

[bruno-garcia]

Example, spec says: queue_overflow :
It would count when hitting this:

sentry-dotnet/src/Sentry/SentryClient.cs

Lines 237 to 239 in 167473c

	_options.LogWarning(
	"The attempt to queue the event failed. Items in queue: {0}",
	Worker.QueuedItems);