feat: add subpath export for resedit

[erickzhao]

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Summarize your changes:

Adds an export for @electron/packager/resedit. We use this utility in Electron's CI, so this lets us do it in a type-safe way for Packager 19:

ref https://www.typescriptlang.org/docs/handbook/modules/reference.html#example-explicit-types-condition