Deploy E2 with 1 NAT Gateway only by default

[shuwu-db]

Adding

1. single_nat_gateway = true
2. one extra public subnet to host the single nat gateway inside the VPC module

for E2 workspace creation

[nfx]

Thank you 🙏🏻

[nfx]

Lgtm

[codecov]

Codecov Report

Merging #870 (31dedba) into master (8947e92) will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #870      +/-   ##
==========================================
+ Coverage   83.78%   83.80%   +0.01%     
==========================================
  Files          92       92              
  Lines        8229     8229              
==========================================
+ Hits         6895     6896       +1     
+ Misses        843      842       -1     
  Partials      491      491              

Impacted Files	Coverage Δ
sqlanalytics/resource_widget.go	86.13% <0.00%> (+0.72%)	⬆️