Handle blob and numbers when parsing the value of 'this' object

[DatGuyJonathan]

What does this PR do?

Blobs and numbers in an instance object look like this in the debug log:
VARIABLE_ASSIGNMENT|[18]|this|{"MyBlob":BLOB(6 bytes),"MyBlob2":BLOB(7 bytes),"MyDateTime":"2018-08-13T21:03:32 .769Z","MyDecimal":3.14,"MyTime":3723004}

It tries to parse that to create child variables for this. It runs into a JSON parse error because the blob value isn't a string, so we can stringify it before the parse then remove the quotes after the parse.

Also, after parsing a number, it gives VS Code a variable whose value isn't a string type so VS Code won't show it. We should save number values as a string.

Result:

What issues does this PR fix or reference?

@W-5173095@

[codecov]

Codecov Report

Merging #558 into develop will increase coverage by 0.02%.
The diff coverage is 100%.

@@             Coverage Diff             @@
##           develop     #558      +/-   ##
===========================================
+ Coverage    73.35%   73.37%   +0.02%     
===========================================
  Files          149      149              
  Lines         5832     5837       +5     
  Branches       917      917              
===========================================
+ Hits          4278     4283       +5     
  Misses        1328     1328              
  Partials       226      226

Impacted Files	Coverage Δ
...dx-apex-replay-debugger/src/core/logContextUtil.ts	90.9% <100%> (+2.02%)	⬆️
...lay-debugger/src/states/variableAssignmentState.ts	89.53% <100%> (+0.37%)	⬆️

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[JimSuplizio]

The fix is pretty straightforward.