Explicitly export types from file.ts

[hmps]

Why

We're using node-hubspot as a part of a NextJS with Typescript. NextJS enforces use of isolatedModules with TS. And the TS compiler threw this error when we tried to build after adding hubspot:

../../node_modules/hubspot/lib/typescript/file.ts:77:29 - error TS1205: Re-exporting a type when the '--isolatedModules' flag is provided requires using 'export type'.

77 export { File, HubspotFile, HubspotImage }                               ~~~~~~~~~~~~

This change addresses the need by:

Adding type to the export statement in file.ts

Contributing guidelines

• Run npm run build

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Thank you for the work you're doing on this package! 🙏

[hmps]

Closing this since #293 is already addressing this issue 🤦