Fix `samples_seen` logging

[callumm-graphcore]

Changelogs

• Account for deviceIterations in logging of samples_seen

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Checklist:

• [ ] Was this PR discussed in an issue? It is recommended to first discuss a new feature into a GitHub issue before opening a PR.
• [ ] Add tests to cover the fixed bug(s) or the new introduced feature(s) (if appropriate).
• [ ] Update the API documentation is a new function is added, or an existing one is deleted.
• [ ] Write concise and explanatory changelogs above.
• [ ] If possible, assign one of the following labels to the PR: feature, fix or test (or ask a maintainer to do it for you).

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discussion related to that PR

[codecov[bot]]

Codecov Report

Merging #483 (cc6adba) into main (983bf6c) will decrease coverage by 1.81%. The diff coverage is 63.15%.

@@            Coverage Diff             @@
##             main     #483      +/-   ##
==========================================
- Coverage   71.45%   69.64%   -1.81%     
==========================================
  Files          93       93              
  Lines        8512     8519       +7     
==========================================
- Hits         6082     5933     -149     
- Misses       2430     2586     +156     

Flag	Coverage Δ
unittests	69.64% <63.15%> (-1.81%)	:arrow_down:

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

Components	Coverage Δ
ipu	29.75% <ø> (-19.40%)	:arrow_down: