Update ByteBufferStream read() to return byte values from 0-255 or -1 if EOF reached.

PiperOrigin-RevId: 269596827

Author: sjudd

library/src/main/java/com/bumptech/glide/util/ByteBufferUtil.java

@@ -194,7 +194,7 @@ public int read() {
       if (!byteBuffer.hasRemaining()) {
         return -1;
       }
-      return byteBuffer.get();
+      return byteBuffer.get() & 0xFF;
     }
 
     @Override