Add auto session tracking

[Tyrrrz]

Related to #1054
Implemented through ISdkIntegration.

Tests omitted.

Note the issue says:

Add an option: EnableAutoSessionTracking with default false until our next major, where we'll flip the default to true.

Should we do that? I added it as true by default because I thought that was the consensus.

[bruno-garcia]

Add an option: EnableAutoSessionTracking with default false until our next major, where we'll flip the default to true.

Should we do that? I added it as true by default because I thought that was the consensus.

I thought it would be best if we only started sending session data on a major release (as we did for Android, JavaScript, iOS) and until then had it as a opt-in feature.

On a server application we'd definitely want that turned off so we need to add to the ASP.NET and ASP.NET Core packages as false.

We can always flip the flag later on, lets start with it as false.

[bruno-garcia]

Looks good other than we should default to false and again on aspnet and aspnetcore default to false again because we'll flip this to true on the core next major.

On the comment we should say: Default is false but will be changed to true on the next major release.

[Tyrrrz]

Updated. Not sure why the tests are failing (seems unrelated but who knows). I don't really have time to debug it today, but I will look into it next week (unless you want to poke at it yourself).

[codecov-commenter]

Codecov Report

Merging #1068 (12778f8) into main (f20b3f0) will decrease coverage by 0.04%.
The diff coverage is 61.53%.

@@            Coverage Diff             @@
##             main    #1068      +/-   ##
==========================================
- Coverage   80.69%   80.64%   -0.05%     
==========================================
  Files         194      195       +1     
  Lines        6284     6294      +10     
  Branches     1397     1399       +2     
==========================================
+ Hits         5071     5076       +5     
- Misses        757      760       +3     
- Partials      456      458       +2     

Impacted Files	Coverage Δ
...try/Integrations/AutoSessionTrackingIntegration.cs	28.57% <28.57%> (ø)
src/Sentry/SentryOptions.cs	91.09% <100.00%> (+0.18%)	⬆️

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[bruno-garcia]

CI passed. thanks