fix the issue that release messages might be missed in certain scenarios

[nobodyiam]

What's the purpose of this PR

fix the issue that release messages might be missed in certain scenarios

Which issue(s) this PR fixes:

Fixes #3806

Brief changelog

1. record the missing release messages when scanning
2. try to reload and notify the missing release messages for certain amount of times

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• 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.
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• Update the CHANGES log.

[codecov-commenter]

Codecov Report

Merging #3819 (970a608) into master (9bd4703) will increase coverage by 0.09%.
The diff coverage is 90.62%.

@@             Coverage Diff              @@
##             master    #3819      +/-   ##
============================================
+ Coverage     50.07%   50.16%   +0.09%     
- Complexity     2457     2466       +9     
============================================
  Files           483      483              
  Lines         14891    14922      +31     
  Branches       1515     1520       +5     
============================================
+ Hits           7456     7486      +30     
  Misses         6908     6908              
- Partials        527      528       +1     

Impacted Files	Coverage Δ
...work/apollo/biz/message/ReleaseMessageScanner.java	82.89% <90.62%> (+9.56%)	⬆️

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[Anilople]

If startId = 2,
a sequence of currentIds in List<ReleaseMessage> messages are [5, 4, 3]

then the for loop will be resolve to

      if (5 - 2 > 1) {
        for (long i = 2 + 1; i < 5; i++) {
          missingReleaseMessages.putIfAbsent(i, 1);
        }
      }

i.e 3 and 4 will put to the missingReleaseMessages though they are in parameter List<ReleaseMessage> messages.

Is this acceptable here?

[nobodyiam]

The release messages are ordered by id, so a sequence of currentIds in List messages would be [3,4,5].

https://github.com/ctripcorp/apollo/blob/9bd47037886468040dacb693db370e6417b31aad/apollo-biz/src/main/java/com/ctrip/framework/apollo/biz/message/ReleaseMessageScanner.java#L102-L113