Removed static variable in get_correct_image_extension to avoid race conditions

12 jobs for 18-load-images-based-on-magic-numbers-instead-of-filename-extension-in-c in 48 minutes and 53 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Build
passed #11186
conda-linux
build_linux_27

00:02:31

passed #11187
conda-linux
build_linux_34

00:04:46

passed #11188
conda-linux
build_linux_35

00:03:33

passed #11189
conda-macosx
build_macosx_27

00:04:07

passed #11190
conda-macosx
build_macosx_34

00:08:27

passed #11191
conda-macosx
build_macosx_35

00:06:12

 
  Test
passed #11192
conda-linux
test_linux_27

00:01:05

73.0%
passed #11193
conda-linux
test_linux_34

00:02:19

73.0%
passed #11194
conda-linux
test_linux_35

00:03:19

73.0%
passed #11195
conda-macosx
test_macosx_27

00:02:06

73.0%
passed #11196
conda-macosx
test_macosx_34

00:04:07

73.0%
passed #11197
conda-macosx
test_macosx_35

00:06:21

73.0%