API: NumericIndex([1 2, 3]).dtype should be int64 on 32-bit systems
- [x] closes #49813
- [x] [Tests added and passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#writing-tests) if fixing a bug or adding a new feature
- [x] All [code checks passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#pre-commit).

thanks @topper-123 