[Enhancement] Enable timeout in dist training

[apacha]

This PR fixes #873:

• Adds option to specify a runtime timeout for distributed training
• Safe conversion of the specified timeout in seconds to timedelta with type-check
• Adding documentation on how to use it

[CLAassistant]

All committers have signed the CLA.

[codecov]

Codecov Report

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Additional details and impacted files

@@           Coverage Diff           @@
##             main     #877   +/-   ##
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  Coverage        ?   78.15%           
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  Files           ?      132           
  Lines           ?     9974           
  Branches        ?     1993           
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  Hits            ?     7795           
  Misses          ?     1842           
  Partials        ?      337           

Flag	Coverage Δ
unittests	78.15% <0.00%> (?)

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[HAOCHENYE]

Thanks for your contributions, he

[HAOCHENYE]

Approved!!!

[jason102811]

Hi @apacha ！First of all, we want to express our gratitude for your significant PR in the MMEngine. Your contribution is highly appreciated, and we are grateful for your efforts in helping improve this open-source project during your personal time. We believe that many developers will benefit from your PR.

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