Update index.mdx (#662)

Fixing a small omission for better clarity.

Author: MarshallJung

docs/get-started/foundations/infrastructure/index.mdx

@@ -364,7 +364,7 @@ If you want to see the spec for your application you can run `nitric spec`:
 nitric spec
 ```
 
-This spec can be automatically forwarded to plugins that generate the IaC configuration and implement a runtime API adapter the chosen services. This way, the IaC configuration is always in sync with the application code and the code always works on the target platform.
+This spec can be automatically forwarded to plugins that generate the IaC configuration and implement a runtime API adapter for the chosen services. This way, the IaC configuration is always in sync with the application code and the code always works on the target platform.
 
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