feat: Add str.extract_many expression

[ritchie46]

closes #17144

[codecov]

Codecov Report

Attention: Patch coverage is 93.82716% with 5 lines in your changes missing coverage. Please review.

Project coverage is 80.72%. Comparing base (0c80788) to head (cb3ba87).

❗ Current head cb3ba87 differs from pull request most recent head 68dc0a6

Please upload reports for the commit 68dc0a6 to get more accurate results.

Files	Patch %	Lines
.../polars-ops/src/chunked_array/strings/find_many.rs	88.00%	3 Missing ⚠️
...rates/polars-plan/src/dsl/function_expr/strings.rs	94.73%	1 Missing ⚠️
py-polars/src/lazyframe/visitor/expr_nodes.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #17304   +/-   ##
=======================================
  Coverage   80.71%   80.72%           
=======================================
  Files        1475     1475           
  Lines      193125   193206   +81     
  Branches     2757     2759    +2     
=======================================
+ Hits       155882   155957   +75     
- Misses      36733    36739    +6     
  Partials      510      510           

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