test: Update error messages to comply with core change

[yinggeh]

What does the PR do?

Update error messages to comply with core change in infer_request.cc.

Checklist

• PR title reflects the change and is of format <commit_type>: <Title>
• Changes are described in the pull request.
• Related issues are referenced.
• Populated github labels field
• Added test plan and verified test passes.
• Verified that the PR passes existing CI.
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• Added succinct git squash message before merging ref.
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Commit Type:

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• build
• ci
• docs
• feat
• fix
• perf
• refactor
• revert
• style
• test

Related PRs:

triton-inference-server/core#364

Test plan:

L0_input_validation--base

• CI Pipeline ID: 15596087

Background

Rewriting byte size validation check logic and changing error message.