fix: properly handle types for presets module (#2945)

Author: wszydlak

presets/index.d.ts

@@ -21,4 +21,4 @@ declare const _default: {
     createCjsPreset: typeof import('../build/presets').createCjsPreset;
     createEsmPreset: typeof import('../build/presets').createEsmPreset;
 };
-export default _default;
+export = _default;

src/presets/__snapshots__/index.spec.ts.snap

@@ -24,7 +24,7 @@ exports[`Jest presets should have the correct types which come from \`ts-jest\`
     createCjsPreset: typeof import('../build/presets').createCjsPreset;
     createEsmPreset: typeof import('../build/presets').createEsmPreset;
 };
-export default _default;
+export = _default;
 "
 `;