fix: Http proxy CORS problem, Keep origin by default.

[dayongxie]

#10692
我修改了一下这段代码，默认情况下不修改Header中的Origin字段，以避免CORS问题
在开启changeOrigin的情况下，http-proxy库会修改Header中的host字段，但是不会修改Origin字段，所以也会导致CORS问题
我加了个判定，changeOrigin开启的时候，修改Origin字段。 这样做既可以让changeOrgin这个控制参数更符合预期，同时避免了CORS问题

修改之后的changeOrigin行为：

• changeOrigin为false：默认行为，不改变请求的origin和host
• changeOrigin为true：请求的origin和host会替换为target的origin
  两种模式都不会有CORS问题

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Name	Status	Preview	Comments	Updated
umi	⬜️ Ignored (Inspect)			Mar 7, 2023 at 4:59PM (UTC)

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (55d6adf) 28.90% compared to head (3bcb75c) 28.90%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #10699   +/-   ##
=======================================
  Coverage   28.90%   28.90%           
=======================================
  Files         458      458           
  Lines       13653    13653           
  Branches     3201     3201           
=======================================
  Hits         3946     3946           
- Misses       9024     9025    +1     
+ Partials      683      682    -1     

Impacted Files	Coverage Δ
packages/bundler-utils/src/proxy.ts	0.00% <0.00%> (ø)

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