fix: incorrect assertion func and json number parse rule

[bbx-winner]

Main Changes

1. fix incorrect assertion functions: greater_than, less_than, greater_or_equals, less_or_equals, adjust the sequence of parameters (actual and expected) of assertion function proto.
2. fix incorrect json number parse rule.

Ref: json.Unmarshal

To unmarshal JSON into an interface value, Unmarshal stores one of these in the interface value:
bool, for JSON booleans
float64, for JSON numbers
string, for JSON strings
[]interface{}, for JSON arrays
map[string]interface{}, for JSON objects
nil for JSON null

3. fix panic when Assertions map key not found.
4. fix unittest bad cases.

[codecov-commenter]

Codecov Report

Merging #83 (76cb479) into main (5ede366) will decrease coverage by 0.05%.
The diff coverage is 50.98%.

@@            Coverage Diff             @@
##             main      #83      +/-   ##
==========================================
- Coverage   55.73%   55.67%   -0.06%     
==========================================
  Files          29       28       -1     
  Lines        3628     3630       +2     
==========================================
- Hits         2022     2021       -1     
  Misses       1461     1461              
- Partials      145      148       +3     

Flag	Coverage Δ
unittests	55.67% <50.98%> (-0.06%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
response.go	69.23% <28.57%> (-2.33%)	⬇️
runner.go	59.40% <41.17%> (-0.36%)	⬇️
internal/builtin/assertion.go	33.85% <60.00%> (+4.93%)	⬆️
parser.go	84.89% <100.00%> (-0.23%)	⬇️
internal/boomer/ulimit_windows.go

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[debugtalk]

还是保留 startswith/endswith 吧；更自然些，而且跟 Python 版本保持一致

[bbx-winner]

fixed

[debugtalk]

代码中不要带字节的内网域名。示例代码还是使用 postman echo 的吧

[bbx-winner]

fixed