Main CL:
1. Copy the code from BE to implement the `str_to_date()` function in FE.
2. `str_to_date("2020-08-08", "%Y-%m-%d %H:%i:%s")` will return `2020-08-08 00:00:00` instead of `2020-08-08`.
Main CL:
1. Copy the code from BE to implement the `str_to_date()` function in FE.
2. `str_to_date("2020-08-08", "%Y-%m-%d %H:%i:%s")` will return `2020-08-08 00:00:00` instead of `2020-08-08`.