Update dependency jest to v25.2.6

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
jest (source)	devDependencies	patch	25.2.4 -> 25.2.6

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Release Notes

facebook/jest

### [`v25.2.6`](https://togithub.com/facebook/jest/blob/master/CHANGELOG.md#​2526) [Compare Source](https://togithub.com/facebook/jest/compare/v25.2.4...v25.2.6) ##### Chore & Maintenance - `[*]` 25.2.5 was published without changes from 25.2.4 - 25.2.6 includes all changes from that version.

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