build(deps-dev): Bump dependency @ui5/linter to ^1.20.15 (#468)

This PR contains the following updates:

| Package | Change |
[Age](https://docs.renovatebot.com/merge-confidence/) |
[Confidence](https://docs.renovatebot.com/merge-confidence/) |
|---|---|---|---|
| [@ui5/linter](https://redirect.github.com/UI5/linter) | [`^1.20.13` →
`^1.20.15`](https://renovatebot.com/diffs/npm/@ui5%2flinter/1.20.14/1.20.15)
|
![age](https://developer.mend.io/api/mc/badges/age/npm/@ui5%2flinter/1.20.15?slim=true)
|
![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/@ui5%2flinter/1.20.14/1.20.15?slim=true)
|

---

### Release Notes

<details>
<summary>UI5/linter (@&#8203;ui5/linter)</summary>

###
[`v1.20.15`](https://redirect.github.com/UI5/linter/blob/HEAD/CHANGELOG.md#12015-2026-03-23)

[Compare
Source](https://redirect.github.com/UI5/linter/compare/v1.20.14...v1.20.15)

##### Dependencies

- **lockfile:** In-range update of npm dependencies
([#&#8203;1027](https://redirect.github.com/UI5/linter/issues/1027))
([5b56052](https://redirect.github.com/UI5/linter/commit/5b560524757981e2ab303fa9684317f8b6733e3b))

</details>

---

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package-lock.json

@@ -19,7 +19,7 @@
 	"devDependencies": {
 		"@eslint/js": "^10.0.1",
 		"@ui5/cli": "^4.0.49",
-		"@ui5/linter": "^1.20.13",
+		"@ui5/linter": "^1.20.15",
 		"@ui5/middleware-code-coverage": "^2.0.3",
 		"eslint": "^10.0.3",
 		"globals": "^17.4.0",