Add missing Get field in UpdateResp struct

[raccone]

Description

Add missing Get field to UpdateResp struct.

Issues Resolved

Closes [BUG] Missing Get field in UpdateResp struct #731

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 14.90%. Comparing base (06a6dc8) to head (cdfe01b).
⚠️ Report is 114 commits behind head on main.

❗ There is a different number of reports uploaded between BASE (06a6dc8) and HEAD (cdfe01b). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (06a6dc8)	HEAD (cdfe01b)
integration	1	0

Additional details and impacted files

@@             Coverage Diff             @@
##             main     #739       +/-   ##
===========================================
- Coverage   57.29%   14.90%   -42.40%     
===========================================
  Files         315      316        +1     
  Lines        9823    10362      +539     
===========================================
- Hits         5628     1544     -4084     
- Misses       2902     8736     +5834     
+ Partials     1293       82     -1211     

Flag	Coverage Δ
integration	?
unit	14.90% <ø> (+2.05%)	⬆️

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

Files with missing lines	Coverage Δ
opensearchapi/api_update.go	0.00% <ø> (-100.00%)	⬇️

... and 305 files with indirect coverage changes

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