Fix typo

Author: khaosdoctor

packages/tsconfig-reference/copy/en/options/allowUnreachableCode.md

@@ -4,7 +4,7 @@ oneline: "Error when code will never be called"
 ---
 
 Set to false to disable warnings about unreachable code.
-These warnings are only about code which is provably unreachable due to the use of JavaScript syntax, for example:
+These warnings are only about code which is probably unreachable due to the use of JavaScript syntax, for example:
 
 ```ts
 function fn(n: number) {