Add setting index value to array

[ppeeou]

What this PR does / why we need it:

we can insert a value at a specific index into arrray yorkie-sdk-js also needs work

Which issue(s) this PR fixes:

Fixes #215

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Additional documentation:

Checklist:

• [x] Added relevant tests or not required
• [x] Didn't break anything

[codecov[bot]]

Codecov Report

Merging #221 (651f853) into main (7c254bb) will decrease coverage by 0.87%. The diff coverage is 27.48%.

@@            Coverage Diff             @@
##             main     #221      +/-   ##
==========================================
- Coverage   57.13%   56.26%   -0.88%     
==========================================
  Files          45       45              
  Lines        3859     3956      +97     
==========================================
+ Hits         2205     2226      +21     
- Misses       1454     1529      +75     
- Partials      200      201       +1     

Impacted Files	Coverage Δ
api/converter/from_pb.go	61.17% <0.00%> (-3.03%)	:arrow_down:
api/converter/to_pb.go	78.51% <0.00%> (-3.98%)	:arrow_down:
pkg/document/json/array.go	35.55% <23.07%> (-0.81%)	:arrow_down:
pkg/document/json/rga_tree_list.go	48.54% <36.70%> (-6.71%)	:arrow_down:
api/converter/to_bytes.go	85.15% <66.66%> (ø)

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[ppeeou]

@hackerwins Is it correct to proceed in this direction🤔?? I want to check yorkie-sdk-js before working

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

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[hackerwins]

The users who requested this feature are not currently seeking it. Therefore, I'll close this PR for now and will reopen it when new requests for the feature arise.