add a config adjust the property source overriden behavior

[shenhuaxin]

What's the purpose of this PR

add a config adjust the property source overriden behavior

Which issue(s) this PR fixes:

Fixes #4367 (comment)

Brief changelog

add property apollo.bootstrap.overrideSystemProperties change apollo property source overriden behavior

Follow this checklist to help us incorporate your contribution quickly and easily:

• Read the Contributing Guide before making this pull request.
• Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
• Write necessary unit tests to verify the code.
• Run mvn clean test to make sure this pull request doesn't break anything.
• Update the CHANGES log.

[github-actions]

CLA Assistant Lite bot All contributors have signed the CLA ✍️ ✅

[shenhuaxin]

I have read the CLA Document and I hereby sign the CLA

[nobodyiam]

Thanks for the contribution! This looks good to me.
However, I think this config should also work for non-spring-boot environment, so we need to rename the config name(apollo.bootstrap is for configs only applicable to spring boot).
Also we need to tell the user how to config it in java-sdk-user-guide(zh, en).

[shenhuaxin]

1. rename apollo.bootstrap.overrideSystemProperties to apollo.overrideSystemProperties
2. add non-spring-boot environment support

[nobodyiam]

I think we could merge this pr after 2.0.1 is released, meanwhile, would you please help to java-sdk-user-guide(zh, en) to tell user how to use this feature?

[shenhuaxin]

sure, i will do it

[codecov-commenter]

Codecov Report

Merging #4377 (60c15ce) into master (1cdbd14) will increase coverage by 0.00%.
The diff coverage is 80.00%.

@@            Coverage Diff            @@
##             master    #4377   +/-   ##
=========================================
  Coverage     53.18%   53.18%           
- Complexity     2674     2676    +2     
=========================================
  Files           489      489           
  Lines         15277    15291   +14     
  Branches       1580     1585    +5     
=========================================
+ Hits           8125     8133    +8     
- Misses         6597     6603    +6     
  Partials        555      555           

Impacted Files	Coverage Δ
...ramework/apollo/core/ApolloClientSystemConsts.java	0.00% <ø> (ø)
...apollo/spring/config/PropertySourcesProcessor.java	93.54% <66.66%> (-2.95%)	⬇️
...ring/boot/ApolloApplicationContextInitializer.java	92.98% <75.00%> (-1.36%)	⬇️
...va/com/ctrip/framework/apollo/util/ConfigUtil.java	82.63% <100.00%> (+0.46%)	⬆️
...framework/apollo/openapi/entity/ConsumerAudit.java	42.42% <0.00%> (-6.07%)	⬇️
...mework/apollo/openapi/service/ConsumerService.java	53.38% <0.00%> (-1.70%)	⬇️
...ervice/service/ReleaseMessageServiceWithCache.java	87.05% <0.00%> (+1.17%)	⬆️

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[nobodyiam]

As 2.1.0 is released, please rebase the code and also update the CHANGES.md.

You may see changes-2.0.1 for reference.

[shenhuaxin]

As 2.1.0 is released, please rebase the code and also update the CHANGES.md.

You may see changes-2.0.1 for reference.

i did something wrong with rebase , and i don't know how to fix it , may i need to create another pr to fix it ?

[nobodyiam]

@shenhuaxin

If rebase doesn't work for you, you may use squash, see the CONTRIBUTING guide.
A new pr is also OK.

[shenhuaxin]

this is a new pr. #4409

i cann't combine the two comimt into one, if i rebase and squash ff1a2e9, push is reject and need merge. can you give me some advice?

[nobodyiam]

this is a new pr. #4409

i cann't combine the two comimt into one, if i rebase and squash ff1a2e9, push is reject and need merge. can you give me some advice?

You may use force push to your shenhuaxin:apollo-pr-override-systemproperties branch. But it's ok as we could squash and merge the pr.