fix(vitest-plugin): update readme with correct minimal vitest version

Author: GuillaumeLagrange

packages/vitest-plugin/README.md

@@ -20,7 +20,7 @@ First, install the plugin [`@codspeed/vitest-plugin`](https://www.npmjs.com/pack
 
 > [!NOTE]
 > The CodSpeed plugin is only compatible with
-> [vitest@1.2.2](https://www.npmjs.com/package/vitest/v/1.2.2)
+> [vitest@3.2](https://www.npmjs.com/package/vitest/v/3.2.4)
 > and above.
 
 ```sh