fix: default values for in 'flashbots_getBundleStatsV2' (closes #42) (#…

…43)

The fields 'considered_by_builders_at', 'sealed_by_builders_at' are
optional, set default derive values (empty array) to avoid the
deserialization error.

src/bundle.rs

@@ -353,8 +353,10 @@ pub struct BundleStats {
     /// When the bundle was received by the bundle API.
     pub received_at: Option<DateTime<Utc>>,
     /// A list of times at which builders selected the bundle to be included in the target block.
+    #[serde(default = "Vec::new")]
     pub considered_by_builders_at: Vec<BuilderEntry>,
     /// A list of times at which builders sealed a block containing the bundle.
+    #[serde(default = "Vec::new")]
     pub sealed_by_builders_at: Vec<BuilderEntry>,
 }