Update readme

Correct spelling mistake #1667

Author: gracekarina

README.md

@@ -653,7 +653,7 @@ components:
 ```
 
 ### Extensions
-This project has a core artifact--`swagger-parser`, which uses Java Service Provider Inteface (SPI) so additional extensions can be added. 
+This project has a core artifact--`swagger-parser`, which uses Java Service Provider Interface (SPI) so additional extensions can be added. 
 
 To build your own extension, you simply need to create a `src/main/resources/META-INF/services/io.swagger.v3.parser.core.extensions.SwaggerParserExtension` file with the full classname of your implementation.  Your class must also implement the `io.swagger.v3.parser.core.extensions.SwaggerParserExtension` interface.  Then, including your library with the `swagger-parser` module will cause it to be triggered automatically.