[BUMP] Update dependency ember-source to ~5.9.0 (junior)

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
ember-source (source)	~5.8.0 -> ~5.9.0

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Release Notes

emberjs/ember.js (ember-source)

v5.9.0

Compare Source

• #​20653 [DEPRECATION] Deprecate (action) and {{action}} in templates per RFC #​1006.
• #​20669 [FEATURE] Make deprecations throw when the until for ember-source has passed per RFC #​0830.
• #​20656 / #​20664 [BUGFIX] Upgrade router_js to support exactOptionalPropertyTypes
• #​20658 Upgrade glimmer-vm to v0.92
• #​20678 Address a missed deprecation introduced in #​20658

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