Remove single-argument function call special-case in formatter

Not sure what this special case was trying to achieve, but it's not right. There's no need to handle function call with a single argument differently than the others.

examples/acceptance_tests/script_context/validators/withdrawals.ak

@@ -8,17 +8,17 @@ use aiken/transaction/credential.{
 fn spend(_datum: Void, _redeemer: Void, ctx: ScriptContext) {
   let alice =
     Inline(
-    VerificationKeyCredential(
-      #"22222222222222222222222222222222222222222222222222222222",
-    ))
-    
+      VerificationKeyCredential(
+        #"22222222222222222222222222222222222222222222222222222222",
+      ),
+    )
 
   let bob =
     Inline(
-    ScriptCredential(
-      #"afddc16c18e7d8de379fb9aad39b3d1b5afd27603e5ebac818432a72",
-    ))
-    
+      ScriptCredential(
+        #"afddc16c18e7d8de379fb9aad39b3d1b5afd27603e5ebac818432a72",
+      ),
+    )
 
   [
     when dict.get(ctx.transaction.withdrawals, alice) is {