🔨 Fix preprocessor table name

Author: phoenixr-codes

README.md

@@ -9,7 +9,7 @@ cargo install mdbook-inline-highlighting
 ## Usage
 
 ```toml
-[preprocessors.inline-highlighting]
+[preprocessor.inline-highlighting]
 
 default-language = "js"
 # Enforce JavaScript syntax highlighting when no language is specified. When this
@@ -38,4 +38,4 @@ for code blocks.
 ## Demo
 
 After cloning this repository and installing the crate, navigate to the `test_book`
-directory and run `mdbook serve` to see the example above in action.
+directory and run `mdbook serve` to see the example above in action.