Merge rust-bitcoin#4227: docs: The quotation marks are incorrect.

a824b79 docs: The quotation marks are incorrect. (RiceChuan)

Pull request description:

  docs: The quotation marks are incorrect.

ACKs for top commit:
  tcharding:
    ACK a824b79
  apoelstra:
    ACK a824b79; successfully ran local tests

Tree-SHA512: b5893fa564af72b31c0893236f29751702764e20e8f05576861e9a47b96c216066838bd48e38277ee1acbdb983a55edc64f9c2466826546f65d70ba309839927

Author: apoelstra

io/src/error.rs

@@ -188,7 +188,7 @@ define_errorkind!(
     WriteZero,
     /// This operation was interrupted.
     Interrupted,
-    /// An error returned when an operation could not be completed because an “end of file” was reached prematurely.
+    /// An error returned when an operation could not be completed because an "end of file" was reached prematurely.
     UnexpectedEof,
     // Note: Any time we bump the MSRV any new error kinds should be added here!
     /// A custom error that does not fall under any other I/O error kind