[DOCS] Add user guide for read_sql

[colin-ho]

No description provided.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 85.59%. Comparing base (24d0831) to head (3be68d6).
Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2226   +/-   ##
=======================================
  Coverage   85.59%   85.59%           
=======================================
  Files          71       71           
  Lines        7586     7594    +8     
=======================================
+ Hits         6493     6500    +7     
- Misses       1093     1094    +1     

Files	Coverage Δ
daft/io/_sql.py	52.38% <ø> (ø)

... and 2 files with indirect coverage changes

[samster25]

Looks great!! 🚀