ascii-art: adding usage case

subjects/ascii-art/README.md

@@ -43,7 +43,7 @@ $$@@$$$$$$$$``````````@@$$@@$$$$$$
   
 ### Banner Format
 
-- Each character has an height of 8 lines.
+- Each character has a height of 8 lines.
 - Characters are separated by a new line `\n`.
 - Here is an example of ' ', '!' and '"'(one dot represents one space) :
 
@@ -81,6 +81,20 @@ $$@@$$$$$$$$``````````@@$$@@$$$$$$
 ### Usage
 
 ```console
+$ go run . ""
+
+$ go run . "\n"
+
+
+$ go run . "Hello\n"
+ _    _          _   _          
+| |  | |        | | | |         
+| |__| |   ___  | | | |   ___   
+|  __  |  / _ \ | | | |  / _ \  
+| |  | | |  __/ | | | | | (_) | 
+|_|  |_|  \___| |_| |_|  \___/  
+
+
 $ go run . "hello"
   _              _   _
  | |            | | | |
@@ -89,7 +103,6 @@ $ go run . "hello"
  | | | | |  __/ | | | | | (_) |
  |_| |_|  \___| |_| |_|  \___/
 
-
 $ go run . "HeLlO"
   _    _          _        _    ____
  | |  | |        | |      | |  / __ \
@@ -98,7 +111,6 @@ $ go run . "HeLlO"
  | |  | | |  __/ | |____  | | | |__| |
  |_|  |_|  \___| |______| |_|  \____/
 
-
 $ go run . "Hello There"
   _    _           _    _                 _______   _
  | |  | |         | |  | |               |__   __| | |
@@ -107,7 +119,6 @@ $ go run . "Hello There"
  | |  | | |  __/  | |  | |  | (_) |         | |    | | | |  |  __/  | |     |  __/
  |_|  |_|  \___|  |_|  |_|   \___/          |_|    |_| |_|   \___|  |_|      \___|
 
-
 $ go run . "1Hello 2There"
      _    _           _    _                       _______   _
  _  | |  | |         | |  | |               ____  |__   __| | |
@@ -116,7 +127,6 @@ $ go run . "1Hello 2There"
 | | | |  | | |  __/  | |  | |  | (_) |      / __/    | |    | | | |  |  __/  | |     |  __/
 |_| |_|  |_|  \___|  |_|  |_|   \___/      |_____|   |_|    |_| |_|   \___|  |_|      \___|
 
-
 $ go run . "{Hello There}"
    __   _    _           _    _                 _______   _                              __
   / /  | |  | |         | |  | |               |__   __| | |                             \ \