[Fix] Update mmcls2torchserve.

[austinmw]

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Motivation

Changed mmcv to mmengine

Modification

Updated for 1.x

Checklist

Before PR:

Used github.dev web-based editor to make quick change, hopefully didn't break any linting rules

• Pre-commit or other linting tools are used to fix the potential lint issues.
• Bug fixes are fully covered by unit tests, the case that causes the bug should be added in the unit tests.
• The modification is covered by complete unit tests. If not, please add more unit test to ensure the correctness.
• The documentation has been modified accordingly, like docstring or example tutorials.

After PR:

• If the modification has potential influence on downstream or other related projects, this PR should be tested with those projects, like MMDet or MMSeg.
• CLA has been signed and all committers have signed the CLA in this PR.

[CLAassistant]

All committers have signed the CLA.

[austinmw]

Apologies, changed to #1190