Bulk delete namespaces in reconfiguration nfr test

[bjee19]

Add bulk delete namespaces function to use in reconfiguration nfr test to improve performance.

Problem: The reconfiguration nfr test takes a very long time to run because we are deleting namespaces individually, we could save a lot of time by bulk deleting them.

Solution: Add a function which deletes multiple namespaces at a single time.

Testing: Ran the nfr test and confirms it still works.

Closes #2376

Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto main
• I will ensure my PR is targeting the main branch and pulling from my branch from my own fork

Release notes

If this PR introduces a change that affects users and needs to be mentioned in the release notes,
please add a brief note that summarizes the change.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.74%. Comparing base (daa2e56) to head (77cc3da).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3402      +/-   ##
==========================================
- Coverage   86.75%   86.74%   -0.01%     
==========================================
  Files         129      129              
  Lines       14928    14928              
  Branches       62       62              
==========================================
- Hits        12951    12950       -1     
- Misses       1826     1827       +1     
  Partials      151      151              

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