expression: separated signatures for PlusIntSig

[Tjianke]

What problem does this PR solve?

Issue Number: close #13973

Problem Summary:

What is changed and how it works?

What's Changed:

builtin_arithmetic.go

How it Works:

Impl vec, separated func sig from original PlusIntSig

Check List

Tests

• Unit test

Side effects

• Performance regression
  • Consumes more CPU
  • Consumes more MEM
• Breaking backward compatibility

Release note

• separated signatures for builtin PlusIngSig

[CLAassistant]

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24 out of 25 committers have signed the CLA.

✅ Tjianke
✅ ichn-hu
✅ crazycs520
✅ lzmhhh123
✅ LittleFall
✅ gauss1314
✅ wshwsh12
✅ Yisaer
✅ luxinle
✅ TszKitLo40
✅ lysu
✅ eurekaka
✅ erwadba
✅ morgo
✅ xuyifangreeneyes
✅ winoros
✅ JmPotato
✅ xhebox
✅ dyzsr
✅ pingyu
✅ time-and-fate
✅ Reminiscent
✅ xiongjiwei
✅ AilinKid
❌ Jianke Tang

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