update dns policy to have immutable strategy field

[maleck13]

What

Makes the routingStrategy immutable. This make migrating between strategies more predictable and sane and also supports the distributd dns work

[codecov]

Codecov Report

Merging #498 (fcfeb88) into main (ece13e8) will increase coverage by 0.35%.
Report is 3 commits behind head on main.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #498      +/-   ##
==========================================
+ Coverage   80.20%   80.56%   +0.35%     
==========================================
  Files          64       64              
  Lines        4492     4492              
==========================================
+ Hits         3603     3619      +16     
+ Misses        600      589      -11     
+ Partials      289      284       -5     

Flag	Coverage Δ
integration	71.66% <ø> (+0.37%)	⬆️
unit	30.03% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
api/v1beta1 (u)	71.42% <ø> (ø)
api/v1beta2 (u)	91.42% <ø> (ø)
pkg/common (u)	88.82% <ø> (ø)
pkg/istio (u)	73.91% <ø> (ø)
pkg/log (u)	94.73% <ø> (ø)
pkg/reconcilers (u)	64.04% <ø> (ø)
pkg/rlptools (u)	79.45% <ø> (ø)
controllers (i)	77.44% <ø> (+0.64%)	⬆️

Files	Coverage Δ
api/v1alpha1/dnspolicy_types.go	81.81% <ø> (ø)

... and 7 files with indirect coverage changes

[mikenairn]

Small suggestion, but nothing that need block a merge.

You need to run make bundle though.

[maleck13]

updated