JSON Codec Updates

[alexanderbez]

Use cdc.JSONMarshaler where applicable instead of the deprecated ctx.Codec.

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[codecov]

Codecov Report

Merging #6444 into master will decrease coverage by 0.01%.
The diff coverage is 6.77%.

@@            Coverage Diff             @@
##           master    #6444      +/-   ##
==========================================
- Coverage   55.79%   55.78%   -0.02%     
==========================================
  Files         465      465              
  Lines       27800    27809       +9     
==========================================
+ Hits        15512    15513       +1     
- Misses      11183    11190       +7     
- Partials     1105     1106       +1     

[tac0turtle]

utACK

[fedekunze]

utACK

[aaronc]

Since this is now using JSONMarshaler we don't actually need to deprecate this in favor of Println do we? Is that right @alexanderbez ?

[alexanderbez]

Good question. I can't recall why the TODO was added. I think we'll still need this, no?

[aaronc]

The main difference is that Println can use ctx.Output if it's set instead of stdout, which I think makes sense anyway. I'm doing some fixes to Println in #6367 and I'm thinking to just update PrintOutput instead and remove Println.