Update local cli executor to use same filename strategy as docker

[jackgerrits]

Why are these changes needed?

• Additionally, this ensures that both stderr and stdout are returned from the executor

Related issue number

Closes #1978

Checks

• I've included any doc changes needed for https://microsoft.github.io/autogen/. See https://microsoft.github.io/autogen/docs/Contribute#documentation to build and test documentation locally.
• I've added tests (if relevant) corresponding to the changes introduced in this PR.
• I've made sure all auto checks have passed.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 90.62500% with 6 lines in your changes are missing coverage. Please review.

Project coverage is 47.98%. Comparing base (99df2c5) to head (d2b65c5).

Files	Patch %	Lines
autogen/coding/local_commandline_code_executor.py	85.00%	4 Missing and 2 partials ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1954       +/-   ##
===========================================
+ Coverage   37.38%   47.98%   +10.59%     
===========================================
  Files          64       65        +1     
  Lines        6879     6910       +31     
  Branches     1518     1647      +129     
===========================================
+ Hits         2572     3316      +744     
+ Misses       4085     3317      -768     
- Partials      222      277       +55     

Flag	Coverage Δ
unittests	47.85% <90.62%> (+10.46%)	⬆️

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[jackgerrits]

@sonichi can you retrigger tests?

[sonichi]

@sonichi can you retrigger tests?

Please make the PR from upstream.