Implemented create anonymous session

[pingu2k4]

Changes

• Implemented create anonymous session

Issue

#100

Checklist before requesting a review

The PR will only be considered when all items within the checklist are marked as complete. Feel free to submit an incomplete draft PR, and add additional commits until you are able to satisfy each item within the checklist.

• I have performed a self-review of my code
• I have submitted at most one additional endpoint implementation
• I have either submitted no additional endpoint implementation, or my implementation covers both client and server SDK's, unless either are marked in the README with a ❌
• I have added applicable tests for my code
• I have updated the README with updated status as a result of this PR

[github-actions]

Package	Line Rate	Branch Rate	Complexity	Health
PinguApps.Appwrite.Client	100%	100%	93	✔
PinguApps.Appwrite.Server	100%	100%	28	✔
PinguApps.Appwrite.Shared	100%	100%	252	✔
Summary	100% (622 / 622)	100% (90 / 90)	373	✔

[github-actions]

Test Results

433 tests  +3   433 ✅ +3   4s ⏱️ ±0s
  3 suites ±0     0 💤 ±0 
  3 files   ±0     0 ❌ ±0 

Results for commit 8c3847e. ± Comparison against base commit ca2c521.