Fix TS type declarations for BasemapName and CartoSlice

[juandjara]

Hello team! I've found some Typescript errors when setting up a new project from the template with Carto3 and Typescript and I saw a very easy correction of them so I created this PR. Let me know if you need any more context, tests, docs or anything like that

There are two changes in this PR:

• changing the type of the createCartoSlice function. Instead of using the custom Reducer type from the types.ts file of the C4R library, we are importing the Reducer type from redux. This is a generic type, and as such, it should be defined as Reducer<any, AnyAction>. The VS Code tooltips let me know about this when I saw that the types for adding the cartoSlice to the store in the TS-template were not matching the redux types.

• changing the type of BasemapName from using & to using |. The & operator in Typescript creates an intersection between types that does not work for joining two enum types together. I learned about that here when I was debugging why VS Code was again complaining in the basemap references scattered across the template. After much research, try, and error, I discovered that you just need to change the & for an | to mean "This type represents values from this enum OR this other enum"

Edit:
Following @Clebal comment and the redux-typescript documentation I've changed the cartoSlice type to further indicate the types of the reducer using Reducer<CartoState, AnyAction>

[coveralls]

Pull Request Test Coverage Report for Build 1591994246

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 70.422%

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Totals
Change from base Build 1583593077:	0.0%
Covered Lines:	963
Relevant Lines:	1278

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💛 - Coveralls

[VictorVelarde]

Code looks good to me, but we should check against Builder, linked locally, before we merge

[Clebal]

@juandjara great job! 🚀

[Clebal]

@VictorVelarde it's ready to check agains builder.

[juandjara]

@Clebal @VictorVelarde thanks for the quick response!
Just FYI, I've checked in my project (Initiative-Vision) and also ran yarn build in the root folder carto-react and everything works fine 👌