fix(freezeV2): optimize Stake2.0 code

[lxcmyf]

What does this PR do?
optimize Stake2.0 code
Why are these changes required?

This PR has been tested by:

• Unit Tests
• Manual Testing

Follow up

Extra details

[codecov-commenter]

Codecov Report

Merging #5134 (a8fc651) into feature/optimize_stake2_code (631c5df) will increase coverage by 4.09%.
The diff coverage is 51.19%.

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@@                        Coverage Diff                         @@
##             feature/optimize_stake2_code    #5134      +/-   ##
==================================================================
+ Coverage                           54.85%   58.95%   +4.09%     
- Complexity                           8260     8767     +507     
==================================================================
  Files                                 841      836       -5     
  Lines                               49714    49585     -129     
  Branches                             5460     5519      +59     
==================================================================
+ Hits                                27273    29233    +1960     
+ Misses                              20310    18049    -2261     
- Partials                             2131     2303     +172     

Impacted Files	Coverage Δ
...main/java/org/tron/core/utils/TransactionUtil.java	44.80% <ø> (-0.32%)	⬇️
...vm/nativecontract/UnDelegateResourceProcessor.java	75.00% <0.00%> (+1.41%)	⬆️
...java/org/tron/core/capsule/TransactionCapsule.java	54.06% <0.00%> (+1.39%)	⬆️
...c/main/java/org/tron/core/db/TransactionTrace.java	76.21% <0.00%> (+6.70%)	⬆️
.../src/main/java/org/tron/common/utils/JsonUtil.java	30.76% <0.00%> (ø)
common/src/main/java/org/tron/core/Constant.java	50.00% <ø> (ø)
.../main/java/org/tron/core/config/args/SeedNode.java	100.00% <ø> (ø)
...n/java/org/tron/common/backup/message/Message.java	40.00% <0.00%> (+40.00%)	⬆️
.../java/org/tron/common/client/WalletGrpcClient.java	0.00% <0.00%> (ø)
...src/main/java/org/tron/core/capsule/utils/RLP.java	25.63% <ø> (+6.72%)	⬆️
... and 60 more

... and 179 files with indirect coverage changes

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