builtinbackup: log during restore as restore, not as backup

[deepthi]

Description

Parameterize the ReportProgress function which is being used by both backup and restore so that we log properly.

Related Issue(s)

Fixes #16482

Checklist

• "Backport to:" labels have been added if this change should be back-ported to release branches
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• Documentation was added or is not required

Deployment Notes

[vitess-bot]

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[mattlord]

LGTM! I only had a couple of nits that you can resolve as you feel best.

[codecov]

Codecov Report

Attention: Patch coverage is 77.77778% with 2 lines in your changes missing coverage. Please review.

Project coverage is 68.62%. Comparing base (59408f9) to head (47b3fb5).

Files	Patch %	Lines
go/vt/mysqlctl/builtinbackupengine.go	77.77%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #16483      +/-   ##
==========================================
- Coverage   68.64%   68.62%   -0.02%     
==========================================
  Files        1551     1551              
  Lines      199471   199474       +3     
==========================================
- Hits       136925   136889      -36     
- Misses      62546    62585      +39     

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