SNOW-1524314 Hide structured types behind context

[sfc-gh-pfus]

Description

SNOW-1524314 Hides structured types behind context. Without using this context, structured types are going to be returned as semistructured types - as strings.

Checklist

• [x] Created tests which fail without the change (if possible)
• [x] Extended the README / documentation, if necessary

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 82.35294% with 6 lines in your changes missing coverage. Please review.

Project coverage is 82.99%. Comparing base (d5655f3) to head (d9a35b0). Report is 1 commits behind head on master.

Files	Patch %	Lines
converter.go	76.00%	6 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #1175 +/- ## ========================================== - Coverage 83.07% 82.99% -0.08% ========================================== Files 54 54 Lines 12578 12605 +27 ========================================== + Hits 10449 10462 +13 - Misses 2129 2143 +14 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.