👷(vitest) Drop unneeded configuration files (#5352)

**Description**

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Follow-up of #5350.

We forgot to drop some unneeded configuration files when moving to
Vitest.

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**Advanced**

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- [x] Category: 👷 Build & CI
- [x] Impacts: Drop unneeded devDependencies

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Author: dubzzz

.changeset/afraid-forks-press.md

@@ -0,0 +1,5 @@
+---
+"@fast-check/vitest": patch
+---
+
+👷(vitest) Drop unneeded configuration files