Fix typo in readme

Closes GH-10.

Reviewed-by: Titus Wormer <[email protected]>

Author: trueberryless

readme.md

@@ -149,7 +149,7 @@ Configuration (TypeScript type).
     — style of quotes to use
 *   `smart` (`Array<string>`, default: `['“”', '‘’']`)
     — list of quotes to see as “smart”
-*   `smart` (`Array<string>`, default: `['"', "'"]`)
+*   `straight` (`Array<string>`, default: `['"', "'"]`)
     — list of quotes to see as “straight”
 
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