Fix read preference for aggregate

[mtrezza]

added failing test cases

[mtrezza]

The fix in parse-community/Parse-SDK-JS#1143 seems to work looking at the mongodb logs.

But I am stuck verifying the read preference in the test case. I don't know what to spyOn.

• spyOn(databaseAdapter.database.serverConfig, 'command').and.callThrough(); doesn't work because command is not called when executing the aggregate query.

• spyOn(databaseAdapter.database.serverConfig, 'cursor').and.callThrough(); doesn't work because cursor is only called 1 time for the schema when executing the aggregate query.

@dplewis Can you help me out on this?

[dplewis]

@davimacedo Is the expert on readPreferences and wrote most of the tests.

[mtrezza]

Alright, got the test case fixed for aggregate.

[mtrezza]

All parse server tests pass locally with the parse SDK merged with fix parse-community/Parse-SDK-JS#1143.

So before merging this PR the new parse SDK has to be released.

[mtrezza]

@acinader ready for review

[codecov]

Codecov Report

Merging #6585 into master will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #6585   +/-   ##
=======================================
  Coverage   93.92%   93.92%           
=======================================
  Files         169      169           
  Lines       11991    11994    +3     
=======================================
+ Hits        11262    11265    +3     
  Misses        729      729           

Impacted Files	Coverage Δ
src/Routers/AggregateRouter.js	100.00% <100.00%> (ø)
src/RestWrite.js	93.64% <0.00%> (-0.17%)	⬇️
src/triggers.js	93.18% <0.00%> (+0.37%)	⬆️

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[acinader]

lgtm

[mtrezza]

Thanks!