fix: add missing config.secret to types

[gierschv]

The release 0.18.0 broke the usage of this library using TypeScript and secret in the config:

error TS2345: Argument of type '{ host: string; secret: string; debug: boolean; }' is not assignable to parameter of type 'Partial<InitConfig>'.
Object literal may only specify known properties, and 'secret' does not exist in type 'Partial<InitConfig>'.

[lsthornt]

Just here to add a +1 confirming that this change works in our codebase, and fixes the type issue noted in the description.

[mdwallis]

Following up on this thread to see if and when the PR will be merged. Thanks in advance.

[semone]

Any plans on merging this one? :)

[tdumitrescu]

Sorry about the delay, v0.18.1 contains the fix