Update docs for VPC integration

[vishesh92]

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Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 25.78%. Comparing base (d597e80) to head (7cda672). Report is 102 commits behind head on main.

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@@            Coverage Diff             @@
##             main     #434      +/-   ##
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+ Coverage   25.66%   25.78%   +0.11%     
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  Files          59       72      +13     
  Lines        5563     6778    +1215     
==========================================
+ Hits         1428     1748     +320     
- Misses       3996     4865     +869     
- Partials      139      165      +26     

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[vishesh92]

@kiranchavala I have updated the docs a little bit. As of now, for using the flavor with-existing-vpc-network requires an extra environment variable for the VPC name. The default & with-kube-vip flavor requires the same environment variables to be defined.

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This pull-request has been approved by: kiranchavala, vishesh92

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[weizhouapache]

/lgtm