fix(stepmodal): fix stepmodal footer logic error; fix update steps props error

[LEEHONCN]

affects: @gio-design/components

fix stepmodal footer logic error; fix update steps props error

ISSUES CLOSED: #211

Related issue link

#211

Changelog

fix stepmodal footer logic error.
unset footer should display default footer.
fix update steps props error, add wayout prop.

Language	Changelog
🇺🇸 English	fix stepmodal footer logic error. fix update steps props error. add wayout prop to fix step path.
🇨🇳 Chinese	修复分步骤弹窗组件footer显示逻辑。修复steps props 变更造成崩溃的问题。修复steps路径不能满足某些情况的问题。

Self check

• Doc is updated/provided or not needed
• Demo is updated/provided or not needed
• TypeScript definition is updated/provided or not needed
• Changelog is provided or not needed

[codecov]

Codecov Report

Merging #226 into master will decrease coverage by 0.06%.
The diff coverage is 84.61%.

@@            Coverage Diff             @@
##           master     #226      +/-   ##
==========================================
- Coverage   70.02%   69.96%   -0.07%     
==========================================
  Files          90       90              
  Lines        2392     2397       +5     
  Branches      611      610       -1     
==========================================
+ Hits         1675     1677       +2     
- Misses        713      716       +3     
  Partials        4        4              

Impacted Files	Coverage Δ
...ages/components/src/components/modal/StepModal.tsx	72.05% <83.33%> (-0.08%)	⬇️
packages/components/src/components/modal/Modal.tsx	98.07% <100.00%> (-1.93%)	⬇️

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