fix some typos in day 20

20_Day_Writing_clean_codes/20_day_writing_clean_codes.md

@@ -196,7 +196,7 @@ const names = ['Asabeneh', 'Mathias', 'Elias', 'Brook']
 // iterating an array using regular for loop
 let len = names.length;
 for(let i = 0; i < len; i++){
-    console.log(names[i].toUpperCas())
+    console.log(names[i].toUpperCase())
 }
 
 
@@ -218,7 +218,7 @@ const person = {
   skills: ['HTML','CSS','JavaScript','React','Node','MongoDB','Python','D3.js'],
   isMarried: true
 }
-for(const key in user) {
+for(const key in person) {
     console.log(key)
 }