Fix for logs showing a string as an array

Some strings were being logged as
```
[w,r,i,t,i,n,g, ,f,i,l,e, ,,[,2,m,,[,1,m,.,e,m,b,a,r,k,/,s,t,a,t,s,.,r,e,p,o,r,t,,[,2,2,m,,[,2,2,m]
```
The fix was applied to the `normalizeInput` method which simply returns if the input was a `typeof` string.

lib/utils/utils.js

@@ -326,6 +326,7 @@ function soliditySha3(arg) {
 }
 
 function normalizeInput(input) {
+  if(typeof input === 'string') return input;
   let args = Object.values(input);
   if (args.length === 0) {
     return "";