adjust the order of message processing

[sonichi]

Why are these changes needed?

move process_all_messages_before_reply after process_last_received_message
move location of tests
bump version to 0.2.17

Related issue number

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

All modified and coverable lines are covered by tests ✅

Project coverage is 59.69%. Comparing base (2912f55) to head (260da57).

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1841       +/-   ##
===========================================
+ Coverage   35.90%   59.69%   +23.79%     
===========================================
  Files          63       63               
  Lines        6637     6637               
  Branches     1456     1581      +125     
===========================================
+ Hits         2383     3962     +1579     
+ Misses       4063     2324     -1739     
- Partials      191      351      +160     

Flag	Coverage Δ
unittests	59.51% <100.00%> (+23.61%)	⬆️

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