Fix build warning: deprecated associated function `chrono::NaiveDateTime::from_timestamp`

[josecelano]

warning: use of deprecated associated function `chrono::NaiveDateTime::from_timestamp`: use `from_timestamp_opt()` instead
  --> src/upgrades/from_v1_0_0_to_v2_0_0/databases/sqlite_v2_0_0.rs:53:41
   |
53 |     let naive_datetime = NaiveDateTime::from_timestamp(timestamp, 0);
   |                                         ^^^^^^^^^^^^^^
   |
   = note: `#[warn(deprecated)]` on by default