fix(sql-lab): SQL Lab commit connection even if no CTA query is made

[snt1017]

SUMMARY

SQL Lab query editor on run commits the connection even if all we do is select a database without CTA enabled. This is not really an issue with most database systems however there are problems when using superset with Mongo BI connector which does not support transactions.

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

TESTING INSTRUCTIONS

ADDITIONAL INFORMATION

• Has associated issue: SQL Lab commit connection even if no CTA query is made #16036
• Required feature flags:
• Changes UI
• Includes DB Migration (follow approval process in SIP-59)
  • Migration is atomic, supports rollback & is backwards-compatible
  • Confirm DB migration upgrade and downgrade tested
  • Runtime estimates and downtime expectations provided
• Introduces new feature or API
• Removes existing feature or API

[betodealmeida]

I think this is fine, and the commit might not even be needed at all (but does no harm) since we close the connection after (exiting the context manager) and open a new one when running select_star.

(I wonder if the commit was needed before we added the closing context manager...)

[rusackas]

Closing/re-opening to kick-start CI 🤞

[codecov]

Codecov Report

Merging #19808 (a76bcb7) into master (3db4a1c) will increase coverage by 1.74%.
The diff coverage is n/a.

❗ Current head a76bcb7 differs from pull request most recent head 04cd48c. Consider uploading reports for the commit 04cd48c to get more accurate results

@@            Coverage Diff             @@
##           master   #19808      +/-   ##
==========================================
+ Coverage   66.54%   68.29%   +1.74%     
==========================================
  Files        1692     1957     +265     
  Lines       64807    75622   +10815     
  Branches     6661     8222    +1561     
==========================================
+ Hits        43129    51643    +8514     
- Misses      19978    21871    +1893     
- Partials     1700     2108     +408     

Flag	Coverage Δ
hive	53.39% <ø> (+0.52%)	⬆️
mysql	78.92% <ø> (-2.98%)	⬇️
postgres	79.00% <ø> (-2.95%)	⬇️
presto	53.32% <ø> (+0.60%)	⬆️
python	82.77% <ø> (+0.39%)	⬆️
sqlite	?
unit	53.44% <ø> (+5.49%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

see 1374 files with indirect coverage changes

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more