chore(deps): update dependency @ember/test-helpers to v4

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
@ember/test-helpers	^3.3.1 -> ^4.0.4
@ember/test-helpers	^2.9.3 \|\| ^3.0.0 -> ^4.0.0

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