fix some interactions between select queries and sub objects

[dstarke]

Fixes some issues introduced by #409, and I think should fix #475.

[codecov]

Codecov Report

Merging #477 into master will increase coverage by 0.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #477      +/-   ##
==========================================
+ Coverage   84.03%   84.04%   +0.01%     
==========================================
  Files          47       47              
  Lines        3795     3798       +3     
  Branches      868      869       +1     
==========================================
+ Hits         3189     3192       +3     
  Misses        606      606

Impacted Files	Coverage Δ
src/ParseQuery.js	94.08% <100%> (+0.05%)	⬆️

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[dstarke]

Ref: parse-community/parse-server#3999
This should address the issues described there.

[flovilmart]

Thanks @dstarke

[flovilmart]

@dstarke I just tested the integration with parse-server and it breaks 2 tests:

    ✗ select nested keys 2 level (issue #1567)
      - TypeError: Cannot read property 'bazoo' of undefined
    ✗ select nested keys 2 level without include (issue #3185)
      - TypeError: Cannot read property 'bazoo' of undefined

I'll have a look