Deal with chrono deprecations

Chrono deprecated several method in 0.4.35 / 0.4.34

- chrono::Duration::days -> chrono::Duration::try_days
  New method was introduced in 0.4.33, so quite recently.
  This requires us to bump minimum chrono version.

- NaiveDateTime::from_timestamp_opt -> DateTime::from_timestamp
  This requires some other changes, because of the switch from
  NaiveDateTime to DateTime.

- NaiveDateTime::timestamp_millis -> .and_utc().timestamp_millis()

I also added a comment explaining the implementation of CqlValueDisplayer
and why it doesn't use existing `impl TryInto<NaiveDate> for CqlDate`.

scylla-cql/Cargo.toml

@@ -21,7 +21,7 @@ thiserror = "1.0"
 num-bigint-03 = { package = "num-bigint", version = "0.3", optional = true }
 num-bigint-04 = { package = "num-bigint", version = "0.4", optional = true }
 bigdecimal-04 = { package = "bigdecimal", version = "0.4", optional = true }
-chrono = { version = "0.4.27", default-features = false, optional = true }
+chrono = { version = "0.4.33", default-features = false, optional = true }
 lz4_flex = { version = "0.11.1" }
 async-trait = "0.1.57"
 serde = { version = "1.0", features = ["derive"], optional = true }

scylla-cql/src/frame/response/result.rs

@@ -1580,10 +1580,10 @@ mod tests {
     #[cfg(feature = "chrono")]
     #[test]
     fn test_datetime_from_cql() {
-        use chrono::{NaiveDate, NaiveDateTime, NaiveTime};
+        use chrono::{DateTime, NaiveDate, NaiveDateTime, NaiveTime};
 
         // 0 when converted to DateTime is 1970-01-01 0:00:00.00
-        let unix_epoch = NaiveDateTime::from_timestamp_opt(0, 0).unwrap().and_utc();
+        let unix_epoch = DateTime::from_timestamp(0, 0).unwrap();
         let date = super::deser_cql_value(&ColumnType::Timestamp, &mut 0i64.to_be_bytes().as_ref())
             .unwrap();
 

scylla-cql/src/frame/value.rs

@@ -489,7 +489,7 @@ impl TryInto<NaiveDate> for CqlDate {
 
         // date_days is u32 then converted to i64 then we subtract 2^31;
         // Max value is 2^31, min value is -2^31. Both values can safely fit in chrono::Duration, this call won't panic
-        let duration_since_unix_epoch = chrono::Duration::days(days_since_unix_epoch);
+        let duration_since_unix_epoch = chrono::Duration::try_days(days_since_unix_epoch).unwrap();
 
         NaiveDate::from_yo_opt(1970, 1)
             .unwrap()