feat: add samples endpoint

[zhaoyongjie]

SUMMARY

Add a new samples endpoint for getting dataset sampling

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

N/A

TESTING INSTRUCTIONS

1. run superset init
2. login Superset
3. open http://localhost:9000/api/v1/dataset/<dataset_id>/samples in browser
4. open http://localhost:9000/api/v1/dataset/<dataset_id>/samples?force=true to force query

ADDITIONAL INFORMATION

• Has associated issue:
• 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

[villebro]

Looks great @zhaoyongjie ! Can we add a few simple tests?

[zhaoyongjie]

Looks great @zhaoyongjie ! Can we add a few simple tests?

Sure, I will do.

[codecov]

Codecov Report

Merging #20170 (2935947) into master (ce01ce9) will decrease coverage by 0.17%.
The diff coverage is 71.05%.

❗ Current head 2935947 differs from pull request most recent head 6323a22. Consider uploading reports for the commit 6323a22 to get more accurate results

@@            Coverage Diff             @@
##           master   #20170      +/-   ##
==========================================
- Coverage   66.44%   66.27%   -0.18%     
==========================================
  Files        1721     1722       +1     
  Lines       64548    64605      +57     
  Branches     6811     6811              
==========================================
- Hits        42890    42815      -75     
- Misses      19925    20057     +132     
  Partials     1733     1733              

Flag	Coverage Δ
hive	?
mysql	82.13% <77.19%> (-0.01%)	⬇️
postgres	82.19% <77.19%> (-0.01%)	⬇️
presto	?
python	82.24% <77.19%> (-0.40%)	⬇️
sqlite	?
unit	?

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

Impacted Files	Coverage Δ
...ugin-chart-table/src/DataTable/hooks/useSticky.tsx	4.21% <0.00%> (ø)
...nd/plugins/plugin-chart-table/src/controlPanel.tsx	16.66% <0.00%> (ø)
superset/constants.py	100.00% <ø> (ø)
...tend/plugins/plugin-chart-table/src/TableChart.tsx	39.00% <33.33%> (ø)
superset/datasets/api.py	86.30% <61.11%> (-2.04%)	⬇️
...ins/plugin-chart-table/src/DataTable/DataTable.tsx	38.54% <66.66%> (ø)
superset/datasets/commands/samples.py	83.33% <83.33%> (ø)
...d/plugins/plugin-chart-table/src/transformProps.ts	64.44% <100.00%> (ø)
superset/datasets/commands/exceptions.py	93.44% <100.00%> (+0.22%)	⬆️
superset/views/base.py	74.01% <100.00%> (+0.08%)	⬆️
... and 18 more

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[villebro]

Second pass comments, mostly nits

[villebro]

LGTM, I look forward to getting rid of samples in the regular chart data endpoint!