refactor(connector): [Adyen] change expiresAt time from string to unixtimestamp (#3506)

Co-authored-by: hyperswitch-bot[bot] <148525504+hyperswitch-bot[bot]@users.noreply.github.com>

crates/common_utils/src/custom_serde.rs

@@ -84,6 +84,53 @@ pub mod iso8601 {
             })
         }
     }
+    /// Use the well-known ISO 8601 format which is without timezone when serializing and deserializing an
+    /// [`Option<PrimitiveDateTime>`][PrimitiveDateTime].
+    ///
+    /// [PrimitiveDateTime]: ::time::PrimitiveDateTime
+    pub mod option_without_timezone {
+        use serde::{de, Deserialize, Serialize};
+        use time::macros::format_description;
+
+        use super::*;
+
+        /// Serialize an [`Option<PrimitiveDateTime>`] using the well-known ISO 8601 format which is without timezone.
+        pub fn serialize<S>(
+            date_time: &Option<PrimitiveDateTime>,
+            serializer: S,
+        ) -> Result<S::Ok, S::Error>
+        where
+            S: Serializer,
+        {
+            date_time
+                .map(|date_time| {
+                    let format =
+                        format_description!("[year]-[month]-[day]T[hour]:[minute]:[second]");
+                    date_time.assume_utc().format(format)
+                })
+                .transpose()
+                .map_err(S::Error::custom)?
+                .serialize(serializer)
+        }
+
+        /// Deserialize an [`Option<PrimitiveDateTime>`] from its ISO 8601 representation.
+        pub fn deserialize<'a, D>(deserializer: D) -> Result<Option<PrimitiveDateTime>, D::Error>
+        where
+            D: Deserializer<'a>,
+        {
+            Option::deserialize(deserializer)?
+                .map(|time_string| {
+                    let format =
+                        format_description!("[year]-[month]-[day]T[hour]:[minute]:[second]");
+                    PrimitiveDateTime::parse(time_string, format).map_err(|_| {
+                        de::Error::custom(format!(
+                            "Failed to parse PrimitiveDateTime from {time_string}"
+                        ))
+                    })
+                })
+                .transpose()
+        }
+    }
 }
 
 /// Use the UNIX timestamp when serializing and deserializing an