Fix typo for doesNotExist

Author: Goooler

assertk/src/jvmMain/kotlin/assertk/assertions/file.kt

@@ -47,7 +47,7 @@ fun Assert<File>.exists() = given { actual ->
 }
 
 /**
- * Asserts the file does not exists.
+ * Asserts the file does not exist.
  */
 fun Assert<File>.doesNotExist() = given { actual ->
     if (!actual.exists()) return

assertk/src/jvmMain/kotlin/assertk/assertions/path.kt

@@ -101,7 +101,7 @@ fun Assert<Path>.exists(vararg options: LinkOption) = given { actual ->
 }
 
 /**
- * Assert that the path does not exists.
+ * Assert that the path does not exist.
  *
  * @param options indicating how symbolic links are handled
  */