ISSUE-3560: Add generate command for bendctl

[kevinw66]

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Summary

Add generate command for bendctl

Changelog

• Improvement

Related Issues

Fixes #3560

Test Plan

Unit Tests

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Codecov Report

Merging #3732 (1ae6f44) into main (9a9351d) will decrease coverage by 0%.
The diff coverage is n/a.

@@          Coverage Diff           @@
##            main   #3732    +/-   ##
======================================
- Coverage     60%     59%    -1%     
======================================
  Files        706     707     +1     
  Lines      37971   38206   +235     
======================================
- Hits       22805   22786    -19     
- Misses     15166   15420   +254     

Impacted Files	Coverage Δ
tools/benchmark/src/main.rs	<1% <ø> (ø)
common/clickhouse-srv/src/binary/mod.rs	0% <0%> (-92%)	⬇️
query/src/users/user_udf.rs	75% <0%> (-19%)	⬇️
query/src/common/mod.rs	70% <0%> (-15%)	⬇️
metasrv/src/store/meta_raft_store.rs	76% <0%> (-3%)	⬇️
common/datavalues/src/data_value_ops.rs	59% <0%> (-2%)	⬇️
...pelines/transforms/transform_aggregator_partial.rs	86% <0%> (-2%)	⬇️
common/dal/src/context.rs	68% <0%> (-2%)	⬇️
common/meta/types/src/table.rs	98% <0%> (ø)
query/src/sql/planner/binder.rs	0% <0%> (ø)
... and 54 more

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[bohutang]

Good.
It would be nice to add a doc for how to use the generate command.

[kevinw66]

Good. It would be nice to add a doc for how to use the generate command.

There is no right place to add document for the command. So I add it in old ontime README.md file

[bohutang]

/lgtm
Thank you @kevinw66 !