fix: Replace errors.Is with errors.As for error type checking

[pandaye]

What type of PR is this?
/kind bug

What this PR does / why we need it:

In multipath.go errors.Is can't handle *exec.ExitError correctly. Use errors.As to ensure capturing and handling non - zero exit code errors.

Which issue(s) this PR fixes:

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Special notes for your reviewer:

Release note:

none

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: pandaye / name: 潘俊汛 (7a9f080)

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[k8s-triage-robot]

The Kubernetes project currently lacks enough active contributors to adequately respond to all PRs.

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