Update dependency redis to v4

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
redis	^3.1.2 -> ^4.0.0

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Release Notes

redis/node-redis

### [`v4.0.0`](https://togithub.com/redis/node-redis/compare/v3.1.2...redis@4.0.0) [Compare Source](https://togithub.com/redis/node-redis/compare/v3.1.2...redis@4.0.0)

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Configuration

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