Change ApplicationContext lifecycle to per node level

[penghuo]

Signed-off-by: penghuo penghuo@gmail.com

Description

1. Currently, ApplicationContext is constructed per request. In this PR. we refactor the ApplicationContext lifecycle to per node level.
2. We change the bean scope to prototype to create PPLService/SQLService per request.

Issues Resolved

• [BUG] Memory usage exceed limit and java.lang.IllegalStateException: resource is not enough to run the query, quit. #611
• [FEATURE] Change trigger when functionRepository created #944

Check List

• New functionality includes testing.
  • All tests pass, including unit test, integration test and doctest
• New functionality has been documented.
  • New functionality has javadoc added
  • New functionality has user manual doc added
• Commits are signed per the DCO using --signoff

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[dai-chen]

Thanks for the changes!