Implement parsing time based on pattern for @ApolloJsonValue

[huxleyliau]

What's the purpose of this PR

Implement parsing time based on pattern for @ApolloJsonValue from #49

Which issue(s) this PR fixes:

Fixes #49

Brief changelog

Make use of Gson's current way of turning a string into a date to make @ApolloJsonValue able to handle time strings according to a given pattern.

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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.
• Write necessary unit tests to verify the code.
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• Update the CHANGES log.

[codecov]

Codecov Report

Attention: 1 lines in your changes are missing coverage. Please review.

Comparison is base (51efea6) 68.58% compared to head (97377d0) 68.63%.

Files	Patch %	Lines
...pring/property/AutoUpdateConfigChangeListener.java	87.50%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main      #53      +/-   ##
============================================
+ Coverage     68.58%   68.63%   +0.04%     
- Complexity     1207     1211       +4     
============================================
  Files           171      171              
  Lines          5198     5209      +11     
  Branches        561      562       +1     
============================================
+ Hits           3565     3575      +10     
  Misses         1372     1372              
- Partials        261      262       +1     

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[nobodyiam]

LGTM