Fix typo in 4ad_01_operators.md (#2219)

* @vog Fix typo in 4ad_01_operators.md

* Apply suggestions from code review

* Apply suggestions from code review

* Update data/tutorials/language/4ad_01_operators.md

---------

Co-authored-by: Cuihtlauac Alvarado <cuihtlauac@users.noreply.github.com>

data/tutorials/language/4ad_01_operators.md

@@ -92,22 +92,23 @@ OCaml has a subtle syntax; not everything is allowed as an operator symbol. An o
 
 **Prefix Operator**
 
-1. First character
-  * `?` `~` or
-  * `!`
-1. Following characters, at least one if the first character is `!`, optional otherwise
-  * `$` `&` `*` `+` `-` `/` `=` `>` `@` `^` `|` or
-  * `%` `<`
+1. First character, either:
+    * `?` `~`
+    * `!`
+1. Following characters, at least one if the first character is `?` or `~`, optional otherwise:
+    * `$` `&` `*` `+` `-` `/` `=` `>` `@` `^` `|`
+    * `%` `<`
 
 **Binary Operator**
-1. First character
-  * `$` `&` `*` `+` `-` `/` `=` `>` `@` `^` `|` or
-  * `%` `<` or
-  * `#`
-2. Following characters, at least one if the first character is `#`, optional otherwise
-  * `$` `&` `*` `+` `-` `/` `=` `>` `@` `^` `|` or
-  * `%` `<` or
-  * `!` `.` `:` `?` `~`
+
+1. First character, either:
+    * `$` `&` `*` `+` `-` `/` `=` `>` `@` `^` `|`
+    * `%` `<`
+    * `#`
+1. Following characters, at least one if the first character is `#`, optional otherwise:
+    * `$` `&` `*` `+` `-` `/` `=` `>` `@` `^` `|`
+    * `%` `<`
+    * `!` `.` `:` `?` `~`
 
 This is defined in the [Prefix and Infix symbols](/manual/lex.html#sss:lex-ops-symbols) section of The OCaml Manual.