fix: remove trailing commas from keystore json

waku/waku_keystore/keyfile.nim

@@ -327,6 +327,22 @@ proc compareMac(m1: openArray[byte], m2: openArray[byte]): bool =
   else:
     return false
 
+type CypherParams = object
+  iv: string
+
+type CryptoNew = object
+  cipher: string
+  cipherparams: CypherParams
+  ciphertext: string
+  kdf: string
+  kdfparams: JsonNode
+  mac: string
+
+type KeystoreEntry = object
+  crypto: CryptoNew
+  id: string
+  version: string
+
 # Creates a keyfile for secret encrypted with password according to the other parameters
 # Returns keyfile in JSON according to Web3 Secure storage format (here, differently than standard, version and id are optional)
 proc createKeyFileJson*(secret: openArray[byte],
@@ -373,20 +389,20 @@ proc createKeyFileJson*(secret: openArray[byte],
 
   let params = ? kdfParams(kdfkind, toHex(salt, true), workfactor)
 
-  let json = %*
-    {
-      "crypto": {
-        "cipher": $cryptkind,
-        "cipherparams": {
-          "iv": toHex(iv, true)
-        },
-        "ciphertext": toHex(ciphertext, true),
-        "kdf": $kdfkind,
-        "kdfparams": params,
-        "mac": toHex(mac.data, true),
-      },
-    }
+  var obj = KeystoreEntry(
+    crypto: CryptoNew(
+        cipher: $cryptkind,
+        cipherparams: CypherParams(
+          iv: toHex(iv, true)
+        ),
+        ciphertext: toHex(ciphertext, true),
+        kdf: $kdfkind,
+        kdfparams: params,
+        mac: toHex(mac.data, true)
+    )
+  )
 
+  let json = %* obj
   if IdInKeyfile:
     json.add("id", %($u))
   if VersionInKeyfile: