Fix: Fixed getArgType reflection value logic

[ChangedenCZD]

What this PR does:
Fixed getArgType reflection value logic.

Source

Demo

Print

Analyse
发现原版指向的类型是struct，如果使用t.Elem()会指向slice
测试了map，结果也是相似的

Conclusion
当getArgType的switch跑到default，且入参为指针时，很可能都会当成一般struct去处理

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

[codecov-commenter]

Codecov Report

Merging #276 (07f2058) into master (8679ff8) will decrease coverage by 0.08%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #276      +/-   ##
==========================================
- Coverage   68.87%   68.79%   -0.09%     
==========================================
  Files          26       26              
  Lines        2911     2903       -8     
==========================================
- Hits         2005     1997       -8     
  Misses        683      683              
  Partials      223      223              

Impacted Files	Coverage Δ
request.go	61.50% <100.00%> (ø)
double.go	86.15% <0.00%> (-1.52%)	⬇️

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[wongoo]

LGTM