[2.4] Simulator end run for all clients

[yhwen]

Fixes # .

Description

Simulator only runs the END_RUN events for those active running clients when the workflow finishes the run. All those swapped out clients need to be swapped in and re-created to run the END_RUN event handling. Most of the applications the END_RUN event handling are not needed when the client processes are not active. Change the simulator to provide an "end_run_for_all" option. The default is false. Only set it to run END_RUN event handling for all clients when explicitly set.

Also change to use multi-threads to run the END_RUN event handling if needed.

Types of changes

• Non-breaking change (fix or new feature that would not break existing functionality).
• Breaking change (fix or new feature that would cause existing functionality to change).
• New tests added to cover the changes.
• Quick tests passed locally by running ./runtest.sh.
• In-line docstrings updated.
• Documentation updated.

[yanchengnv]

The end_run processing logic is very hard to understand. Please improve.

[yanchengnv]

Looks good now.

[yhwen]

/build

[yhwen]

/build

[SYangster]

/build