[fix] Fix create/update opertions if leftover DNS entries are found

[amold1]

What this PR does / why we need it:
Currently if an old un-removed DNS A Record is found that matches the name and IP exactly, we look for a TXT record to determine ownership. If TXT record was somehow cleaned in the previous run, controller errors out.
With this fix, if the exact DNS record is found, we leave it alone and push a new TXT record for future updates and deletes.

(This situation arises when we create the cluster with the same name and dns unique id. If the dns record deletion failed on cluster removal, you would see this bug. The IP matches because linode keeps/caches some IPs for the account so you might end up with the same IP being re-assigned)

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 68.02%. Comparing base (a417bbc) to head (fab635e).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #424      +/-   ##
==========================================
- Coverage   68.08%   68.02%   -0.07%     
==========================================
  Files          60       60              
  Lines        3393     3374      -19     
==========================================
- Hits         2310     2295      -15     
+ Misses        946      944       -2     
+ Partials      137      135       -2     

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