Fix ExprCollectionValue serialization bug

[penghuo]

Issue #, if available: N/A

Description of changes:

1. Fix ExprCollectionValue serialization bug.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[chloe-zh]

LGTM, thanks for the fix!

[codecov]

Codecov Report

Merging #859 (4185f62) into develop (200a76d) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             develop     #859   +/-   ##
==========================================
  Coverage      99.85%   99.85%           
- Complexity      2115     2116    +1     
==========================================
  Files            214      214           
  Lines           4738     4742    +4     
  Branches         308      309    +1     
==========================================
+ Hits            4731     4735    +4     
  Misses             5        5           
  Partials           2        2           

Impacted Files	Coverage Δ	Complexity Δ
...sticsearch/sql/data/model/ExprCollectionValue.java	100.00% <100.00%> (ø)	14.00 <2.00> (+1.00)

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