Fix test_subgraph skipif

[leezu]

Fix a typo in #18252

[mxnet-bot]

Hey @leezu , Thanks for submitting the PR
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[mseth10]

LGTM

[mseth10]

@mxnet-bot run ci [miscellaneous, centos-gpu, unix-gpu]

[mxnet-bot]

Unauthorized access detected.
Only following 3 categories can trigger CI :
PR Author, MXNet Committer, Jenkins Admin.

[leezu]

@mxnet-bot run ci [miscellaneous, centos-gpu, unix-gpu]

[mxnet-bot]

Jenkins CI successfully triggered : [miscellaneous, unix-gpu, centos-gpu]

[leezu]

@mxnet-bot run ci [miscellaneous]

[mxnet-bot]

Jenkins CI successfully triggered : [miscellaneous]

[mseth10]

@leezu can we merge this?