build: cancel previous github action runs

[ktmud]

SUMMARY

CI has been slow recently, partly because of long running queue.

Each new commits to an open PR triggers a new CI job. Let's see if cancelling previous runs helps speed things up.

Ref: https://github.com/styfle/cancel-workflow-action

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

N/A

TEST PLAN

CI should work

ADDITIONAL INFORMATION

• Has associated issue:
• Changes UI
• Requires DB Migration.
• Confirm DB Migration upgrade and downgrade tested.
• Introduces new feature or API
• Removes existing feature or API

[codecov-io]

Codecov Report

Merging #11940 (e474f43) into master (98dc657) will increase coverage by 0.18%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #11940      +/-   ##
==========================================
+ Coverage   67.63%   67.82%   +0.18%     
==========================================
  Files         932      937       +5     
  Lines       45221    45520     +299     
  Branches     4335     4341       +6     
==========================================
+ Hits        30587    30872     +285     
- Misses      14531    14545      +14     
  Partials      103      103              

Flag	Coverage Δ
cypress	55.10% <ø> (+0.25%)	⬆️
javascript	62.99% <ø> (-0.15%)	⬇️
python	64.37% <ø> (+0.19%)	⬆️

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

Impacted Files	Coverage Δ
...ntend/src/dashboard/components/PropertiesModal.jsx	83.03% <0.00%> (-1.79%)	⬇️
superset/config.py	89.00% <0.00%> (-1.07%)	⬇️
...end/src/SqlLab/components/TemplateParamsEditor.jsx	88.88% <0.00%> (-0.31%)	⬇️
superset-frontend/src/chart/Chart.jsx	58.18% <0.00%> (ø)
superset-frontend/src/common/components/index.tsx	100.00% <0.00%> (ø)
...erset-frontend/src/datasource/DatasourceEditor.jsx	73.59% <0.00%> (ø)
...erset-frontend/src/profile/components/Security.tsx	100.00% <0.00%> (ø)
...-frontend/src/common/components/common.stories.tsx	0.00% <0.00%> (ø)
superset-frontend/src/common/components/Badge.tsx	100.00% <0.00%> (ø)
superset/sql_validators/postgres.py	100.00% <0.00%> (ø)
... and 12 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 98dc657...e474f43. Read the comment docs.

[graceguo-supercat]

LGTM! thank you!