fix: conditionally get descriptor on hmr

[sxzz]

Description

Imported the 'fs' module and added a conditional check using fs.existsSync() to ensure that the getDescriptor() function is only called when the file exists. This prevents errors when the file doesn't exist and improves the overall functionality.

Additional context

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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