upgrade: update pnpm to v8.15.7 (#507)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [pnpm](https://pnpm.io) ([source](https://togithub.com/pnpm/pnpm)) |
[`8.15.6` ->
`8.15.7`](https://renovatebot.com/diffs/npm/pnpm/8.15.6/8.15.7) |
[![age](https://developer.mend.io/api/mc/badges/age/npm/pnpm/8.15.7?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/npm/pnpm/8.15.7?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/npm/pnpm/8.15.6/8.15.7?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/pnpm/8.15.6/8.15.7?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>pnpm/pnpm (pnpm)</summary>

###
[`v8.15.7`](https://togithub.com/pnpm/pnpm/compare/v8.15.6...v8.15.7)

[Compare
Source](https://togithub.com/pnpm/pnpm/compare/v8.15.6...v8.15.7)

</details>

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package.json

@@ -17,5 +17,5 @@
     "prettier": "^3.0.3",
     "prettier-plugin-packagejson": "^2.4.5"
   },
-  "packageManager": "pnpm@8.15.6"
+  "packageManager": "pnpm@8.15.7"
 }