Update dependency @types/jest to v26

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
@types/jest	devDependencies	major	^25.1.0 -> ^26.0.0

---

Renovate configuration

:date: Schedule: "before 7am every weekday" in timezone Europe/Brussels.

:vertical_traffic_light: Automerge: Enabled.

:recycle: Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

:no_bell: Ignore: Close this PR and you won't be reminded about this update again.

---

• [ ] If you want to rebase/retry this PR, check this box

---

This PR has been generated by WhiteSource Renovate. View repository job log here.