refactor(csharp): implement SDK version handling in login requests

[lukaszzborek]

• change version passing during login from static value to assembly version
• change PackageVersion attribute to Version in .csproj

---

PackageVersion attribute was changed because it is not visible in the assembly. If PackageVersion attribute is not set, Version attribute is used as the default.
Also I checked CI, and in all places, I see PackageVersion|Version check, so no need to change it

[codecov]

Codecov Report

❌ Patch coverage is 85.71429% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 68.47%. Comparing base (ff4716e) to head (c0cd3ed).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
foreign/csharp/Iggy_SDK/Utils/SdkVersion.cs	66.66%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #2937      +/-   ##
============================================
- Coverage     70.28%   68.47%   -1.82%     
+ Complexity      862      729     -133     
============================================
  Files          1028     1052      +24     
  Lines         85280    84168    -1112     
  Branches      62656    60935    -1721     
============================================
- Hits          59940    57633    -2307     
- Misses        22828    24178    +1350     
+ Partials       2512     2357     -155     

Flag	Coverage Δ
csharp	67.43% <85.71%> (-0.19%)	⬇️

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Files with missing lines	Coverage Δ
...DK/IggyClient/Implementations/HttpMessageStream.cs	71.72% <100.00%> (ø)
...SDK/IggyClient/Implementations/TcpMessageStream.cs	76.33% <100.00%> (ø)
foreign/csharp/Iggy_SDK/Utils/SdkVersion.cs	66.66% <66.66%> (ø)

... and 139 files with indirect coverage changes

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