Fix parsing sequences of H256s in a matchinglist via agent settings (#…

…3180)

### Description

Upon trying to use a blacklist with an array of H256s as the
`recipientAddress`, was getting a panic:
```
running 1 test
parse_value: Array [Object {"destinationdomain": Number(11155111), "origindomain": Number(1399811151), "recipientaddress": Array [String("0x6AD4DEBA8A147d000C09de6465267a9047d1c217"), String("0x6AD4DEBA8A147d000C09de6465267a9047d1c218")], "senderaddress": Array [String("0x6AD4DEBA8A147d000C09de6465267a9047d1c217"), String("0x6AD4DEBA8A147d000C09de6465267a9047d1c218")]}] "Expected matching list"
thread 'settings::matching_list::test::supports_sequence_h256s' panicked at 'called `Result::unwrap()` on an `Err` value: ConfigParsingError([(ConfigPath([]), Expected matching list

Caused by:
    invalid type: string "0x6AD4DEBA8A147d000C09de6465267a9047d1c217", expected a borrowed string

Location:
    /Users/trevor/abacus-monorepo/rust/hyperlane-base/src/settings/parser/json_value_parser.rs:259:14)])', agents/relayer/src/settings/matching_list.rs:473:60
stack backtrace:
   0: rust_begin_unwind
             at /rustc/d5c2e9c342b358556da91d61ed4133f6f50fc0c3/library/std/src/panicking.rs:593:5
   1: core::panicking::panic_fmt
             at /rustc/d5c2e9c342b358556da91d61ed4133f6f50fc0c3/library/core/src/panicking.rs:67:14
   2: core::result::unwrap_failed
             at /rustc/d5c2e9c342b358556da91d61ed4133f6f50fc0c3/library/core/src/result.rs:1651:5
   3: core::result::Result<T,E>::unwrap
             at /rustc/d5c2e9c342b358556da91d61ed4133f6f50fc0c3/library/core/src/result.rs:1076:23
   4: relayer::settings::matching_list::test::supports_sequence_h256s
             at ./src/settings/matching_list.rs:473:9
   5: relayer::settings::matching_list::test::supports_sequence_h256s::{{closure}}
             at ./src/settings/matching_list.rs:459:34
   6: core::ops::function::FnOnce::call_once
             at /rustc/d5c2e9c342b358556da91d61ed4133f6f50fc0c3/library/core/src/ops/function.rs:250:5
   7: core::ops::function::FnOnce::call_once
             at /rustc/d5c2e9c342b358556da91d61ed4133f6f50fc0c3/library/core/src/ops/function.rs:250:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
test settings::matching_list::test::supports_sequence_h256s ... FAILED
```

Honestly not too sure about the implications of this being a String vs
&str

### Drive-by changes

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### Related issues

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- Fixes #[issue number here]
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### Backward compatibility

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### Testing

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rust/agents/relayer/src/settings/matching_list.rs

@@ -186,8 +186,8 @@ impl<'de> Visitor<'de> for FilterVisitor<H256> {
         A: SeqAccess<'de>,
     {
         let mut values = Vec::new();
-        while let Some(i) = seq.next_element::<&str>()? {
-            values.push(parse_addr(i)?)
+        while let Some(i) = seq.next_element::<String>()? {
+            values.push(parse_addr(&i)?)
         }
         Ok(Self::Value::Enumerated(values))
     }
@@ -454,4 +454,19 @@ mod test {
             r#"[{"origindomain":1399811151,"senderaddress":"DdTMkk9nuqH5LnD56HLkPiKMV3yB3BNEYSQfgmJHa5i7","destinationdomain":11155111,"recipientaddress":"0x6AD4DEBA8A147d000C09de6465267a9047d1c217"}]"#,
         ).unwrap();
     }
+
+    #[test]
+    fn supports_sequence_h256s() {
+        let json_str = r#"[{"origindomain":1399811151,"senderaddress":["0x6AD4DEBA8A147d000C09de6465267a9047d1c217","0x6AD4DEBA8A147d000C09de6465267a9047d1c218"],"destinationdomain":11155111,"recipientaddress":["0x6AD4DEBA8A147d000C09de6465267a9047d1c217","0x6AD4DEBA8A147d000C09de6465267a9047d1c218"]}]"#;
+
+        // Test parsing directly into MatchingList
+        serde_json::from_str::<MatchingList>(json_str).unwrap();
+
+        // Test parsing into a Value and then into MatchingList, which is the path used
+        // by the agent config parser.
+        let val: serde_json::Value = serde_json::from_str(json_str).unwrap();
+        let value_parser =
+            hyperlane_base::settings::parser::ValueParser::new(Default::default(), &val);
+        crate::settings::parse_matching_list(value_parser).unwrap();
+    }
 }