feat(Theme): add font weight

[nianxiongdi]

添加font weight变量，在原来的基础上添加4个变量，在配置平台使用，用来让用户在组件中选择修改字重，定义字重：https://fusion.design/design/style/font

[codecov]

Codecov Report

Merging #857 into feat/1.16.0 will increase coverage by 6.58%.
The diff coverage is n/a.

@@               Coverage Diff               @@
##           feat/1.16.0     #857      +/-   ##
===============================================
+ Coverage        84.77%   91.35%   +6.58%     
===============================================
  Files              244      244              
  Lines            11291    14058    +2767     
  Branches          2813     4418    +1605     
===============================================
+ Hits              9572    12843    +3271     
- Misses             910     1196     +286     
+ Partials           809       19     -790

Impacted Files	Coverage Δ
src/menu/view/radio-item.jsx	66.66% <0%> (-33.34%)	⬇️
src/menu/view/checkbox-item.jsx	75% <0%> (-25%)	⬇️
src/util/dom.js	87.87% <0%> (-12.13%)	⬇️
src/tab/tabs/utils.js	86.95% <0%> (-6.38%)	⬇️
src/table/fixed/body.jsx	66.66% <0%> (-6.07%)	⬇️
src/table/base/resize.jsx	90% <0%> (-5.24%)	⬇️
src/slider/slick/mixins/trackHelper.js	86.36% <0%> (-2.68%)	⬇️
src/upload/runtime/html5-uploader.jsx	88.23% <0%> (-2.68%)	⬇️
src/validate/util.js	85.07% <0%> (-2.65%)	⬇️
src/select/util.js	85.6% <0%> (-2.28%)	⬇️
... and 206 more

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