Case insensitive match for ForkName (sigp#2587)

## Issue Addressed

sigp#2583

## Proposed Changes

Case insensitive match on `fork_name` when calling `ForkName::from_str`

## Additional Info

N/A

consensus/types/src/fork_name.rs

@@ -58,7 +58,7 @@ impl FromStr for ForkName {
     type Err = ();
 
     fn from_str(fork_name: &str) -> Result<Self, ()> {
-        Ok(match fork_name {
+        Ok(match fork_name.to_lowercase().as_ref() {
             "phase0" | "base" => ForkName::Base,
             "altair" => ForkName::Altair,
             _ => return Err(()),
@@ -110,4 +110,22 @@ mod test {
             assert_eq!(fork.previous_fork(), Some(prev_fork));
         }
     }
+
+    #[test]
+    fn fork_name_case_insensitive_match() {
+        assert_eq!(ForkName::from_str("BASE"), Ok(ForkName::Base));
+        assert_eq!(ForkName::from_str("BaSe"), Ok(ForkName::Base));
+        assert_eq!(ForkName::from_str("base"), Ok(ForkName::Base));
+
+        assert_eq!(ForkName::from_str("PHASE0"), Ok(ForkName::Base));
+        assert_eq!(ForkName::from_str("PhAsE0"), Ok(ForkName::Base));
+        assert_eq!(ForkName::from_str("phase0"), Ok(ForkName::Base));
+
+        assert_eq!(ForkName::from_str("ALTAIR"), Ok(ForkName::Altair));
+        assert_eq!(ForkName::from_str("AlTaIr"), Ok(ForkName::Altair));
+        assert_eq!(ForkName::from_str("altair"), Ok(ForkName::Altair));
+
+        assert_eq!(ForkName::from_str("NO_NAME"), Err(()));
+        assert_eq!(ForkName::from_str("no_name"), Err(()));
+    }
 }