make simple root page update optional

[LeoQuote]

Genrating simple root page is sometimes time-consuming , and it is not really used by pip( pip will use https://pypi.org/simple/my-package/ directly ), thus not so important, this option could lead to an unsynced simple root page , but no critical damage is made.

[codecov]

Codecov Report

Merging #1145 (73398f0) into main (25a7c2d) will increase coverage by 0.01%.
The diff coverage is 87.50%.

@@            Coverage Diff             @@
##             main    #1145      +/-   ##
==========================================
+ Coverage   79.48%   79.50%   +0.01%     
==========================================
  Files          16       16              
  Lines        2608     2610       +2     
  Branches      476      477       +1     
==========================================
+ Hits         2073     2075       +2     
  Misses        385      385              
  Partials      150      150              

Impacted Files	Coverage Δ
src/bandersnatch/main.py	75.24% <50.00%> (+0.24%)	⬆️
src/bandersnatch/mirror.py	83.66% <100.00%> (+0.03%)	⬆️

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[cooperlees]

Awesome stuff with a great unit test. Lets just make the argument name a little more explicit so its harder to mis understand.

[cooperlees]

Thanks for your contribution! This could be useful for peoples.