[feat] Templating changes to enable VPC only backend by default

[komer3]

What this PR does / why we need it:

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

Special notes for your reviewer:

TODOs:

• squashed commits
• includes documentation
• adds unit tests
• adds or updates e2e tests

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 63.20%. Comparing base (6e6db1b) to head (551dae0).
⚠️ Report is 9 commits behind head on vpc-only-backends.

Additional details and impacted files

@@                Coverage Diff                 @@
##           vpc-only-backends     #825   +/-   ##
==================================================
  Coverage              63.20%   63.20%           
==================================================
  Files                     71       71           
  Lines                   7359     7359           
==================================================
  Hits                    4651     4651           
  Misses                  2435     2435           
  Partials                 273      273           

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