[fs.op.copy] Replace non-codeblocks with outputblocks (#7146)

Author: frederick-vs-ja

source/iostreams.tex

@@ -17372,16 +17372,16 @@
 \pnum
 \begin{example}
 Given this directory structure:
-\begin{codeblock}
+\begin{outputblock}
 /dir1
   file1
   file2
   dir2
     file3
-\end{codeblock}
+\end{outputblock}
 
 Calling \tcode{copy("/dir1", "/dir3")} would result in:
-\begin{codeblock}
+\begin{outputblock}
 /dir1
   file1
   file2
@@ -17390,10 +17390,10 @@
 /dir3
   file1
   file2
-\end{codeblock}
+\end{outputblock}
 
 Alternatively, calling \tcode{copy("/dir1", "/dir3", copy_options::recursive)} would result in:
-\begin{codeblock}
+\begin{outputblock}
 /dir1
   file1
   file2
@@ -17404,7 +17404,7 @@
   file2
   dir2
     file3
-\end{codeblock}
+\end{outputblock}
 \end{example}
 \end{itemdescr}