Remove SDK docs due to migration to main docs

[marcduiker]

Description

Remove SDK docs due to migration to main docs. This is the Main Docs PR that adds the Go SDK docs:
dapr/docs#4951 (The Docs PR needs to be merged first before this one).

Issue reference

Please reference the issue this PR will close: dapr/docs#4943

Checklist

Please make sure you've completed the relevant tasks for this PR, out of the following list:

• Code compiles correctly
• Created/updated tests
• Extended the documentation

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 55.73%. Comparing base (6c59092) to head (f1f4c91).
⚠️ Report is 35 commits behind head on main.

❗ There is a different number of reports uploaded between BASE (6c59092) and HEAD (f1f4c91). Click for more details.

HEAD has 3 uploads less than BASE

Flag	BASE (6c59092)	HEAD (f1f4c91)
	4	1

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #790      +/-   ##
==========================================
- Coverage   62.52%   55.73%   -6.79%     
==========================================
  Files          56       58       +2     
  Lines        4139     3694     -445     
==========================================
- Hits         2588     2059     -529     
- Misses       1425     1498      +73     
- Partials      126      137      +11     

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[marcduiker]

Not sure why code coverage went down since I only removed markdown files 😬 .