Add diffblue deeptest unit tests for com.alibaba.fastjson

[JohnLBergqvist]

The test cases contained in this PR were automatically generated by Diffblue's Deeptest software

Please feel free to merge them into your repository.

The tests for fastjson can be viewed in more detail (with a trace view & step-through execution) at http://diff.blue/demo

We would be delighted with any feedback you have on these tests.

[CLAassistant]

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[codecov-io]

Codecov Report

Merging #1956 into master will decrease coverage by <.01%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##             master   #1956      +/-   ##
===========================================
- Coverage     81.01%     81%   -0.01%     
+ Complexity     6220    6218       -2     
===========================================
  Files           137     137              
  Lines         23125   23125              
  Branches       5356    5356              
===========================================
- Hits          18735   18733       -2     
- Misses         3038    3039       +1     
- Partials       1352    1353       +1

Impacted Files	Coverage Δ	Complexity Δ
...com/alibaba/fastjson/parser/JSONReaderScanner.java	72.61% <0%> (-1.28%)	44% <0%> (-1%)

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[kimmking]

@JohnBergqvist how to generate deeptests?

[JohnLBergqvist]

@kimmking Hopefully this white paper: https://www.diffblue.com/papers/overview.pdf should explain what Deeptest is. If you would like to know more, we would be happy to arrange a call to discuss further?