Add timm reference in README.md

[kaushikb11]

What does this PR do?

Fixes # (issue)

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[codecov]

Codecov Report

Merging #291 (0821d9d) into master (9868971) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #291   +/-   ##
=======================================
  Coverage   84.26%   84.26%           
=======================================
  Files          74       74           
  Lines        3577     3577           
=======================================
  Hits         3014     3014           
  Misses        563      563           

Flag	Coverage Δ
unittests	84.26% <ø> (ø)

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