Fix public key validation bug

SignalServiceKit/src/Loki/ECKeyPair.swift

@@ -14,8 +14,8 @@ public extension ECKeyPair {
         // Check that it's a valid hexadecimal encoding
         let allowedCharacters = CharacterSet(charactersIn: "0123456789ABCDEF")
         guard candidate.uppercased().unicodeScalars.allSatisfy({ allowedCharacters.contains($0) }) else { return false }
-        // Check that it has either length 33 and a leading "05" or length 32
-        guard (candidate.count == 33 && candidate.hasPrefix("05")) || candidate.count == 32 else { return false }
+        // Check that it has either length 66 and a leading "05" or length 64
+        guard (candidate.count == 66 && candidate.hasPrefix("05")) || candidate.count == 64 else { return false }
         // It appears to be a valid public key
         return true
     }