feat(eslint.config.js): ignore JSON files in tests

This commit updates the eslint configuration to ignore JSON files
located in the tests directory. This is done to prevent linting errors
from being thrown for these files, as they are not meant to adhere to
the project's JavaScript/TypeScript style guidelines.

eslint.config.js

@@ -2,7 +2,7 @@ import { ryoppippi } from '@ryoppippi/eslint-config';
 
 export default ryoppippi({
 	svelte: false,
-	ignores: ['tsdown.config.ts', 'vite.config.ts'],
+	ignores: ['tsdown.config.ts', 'vite.config.ts', 'tests/**/*.json'],
 	typescript: {
 		tsconfigPath: './tsconfig.json',
 		overrides: {