fix field type is datetime equals fail

[jsbxyyx]

fix: #1116

[codecov-io]

Codecov Report

Merging #1117 into develop will decrease coverage by <.01%.
The diff coverage is 33.33%.

@@              Coverage Diff              @@
##             develop    #1117      +/-   ##
=============================================
- Coverage      41.87%   41.87%   -0.01%     
  Complexity      1361     1361              
=============================================
  Files            243      243              
  Lines          10106    10112       +6     
  Branches        1319     1321       +2     
=============================================
+ Hits            4232     4234       +2     
- Misses          5327     5329       +2     
- Partials         547      549       +2

Impacted Files	Coverage Δ	Complexity Δ
.../java/io/seata/rm/datasource/DataCompareUtils.java	84.21% <33.33%> (-5.99%)	24 <0> (ø)

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[slievrly]

LGTM

[slievrly]

@jsbxyyx modify your pr title，will be as commit log.

[ujjboy]

I think this is not a real solution, the reason for #1116 is the json serialization loses millisecond precision.

[jsbxyyx]

@ujjboy

the problem is not json serialization loses millisecond precision, you look the value type afterRecords is String, currentRecords is Timestamp

I also think this is not a good solution. the problem solution requires a serialization method that retain the type.

[xingfudeshi]

LGTM.

[zhangthen]

The actual reason is that the serialization protocol(fastjson) used by undo log is not a good one.

We can fix it with this temporary solution first.