Fixed docs for WandbLogger

[hassiahk]

What does this PR do?

Fixed a small bug with the WandbLogger docs.

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[codecov]

Codecov Report

Merging #5128 (211bca7) into master (e721b1f) will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master   #5128   +/-   ##
======================================
  Coverage      93%     93%           
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  Files         134     134           
  Lines        9928    9928           
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  Hits         9242    9242           
  Misses        686     686