Fix JpegDecoderTests.Decode_IsCancellable

[antonfirsov]

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Description

Fixes #1414 (hopefully)

[codecov]

Codecov Report

Merging #1415 (73454f5) into master (adf56a4) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1415   +/-   ##
=======================================
  Coverage   82.99%   82.99%           
=======================================
  Files         692      692           
  Lines       31189    31189           
  Branches     3578     3578           
=======================================
  Hits        25884    25884           
  Misses       4582     4582           
  Partials      723      723           

Flag	Coverage Δ
unittests	82.99% <ø> (ø)

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[JimBobSquarePants]

This looks like it works so I'm merging it. I've had to retrigger the build a lot recently!