Markdown code blocks migration part 7 (#20547)

lib/posix/inotify.nim

@@ -75,11 +75,11 @@ proc inotify_rm_watch*(fd: cint; wd: cint): cint {.cdecl,
 
 iterator inotify_events*(evs: pointer, n: int): ptr InotifyEvent =
   ## Abstract the packed buffer interface to yield event object pointers.
-  ##
-  ## .. code-block:: Nim
+  ##   ```Nim
   ##   var evs = newSeq[byte](8192)        # Already did inotify_init+add_watch
   ##   while (let n = read(fd, evs[0].addr, 8192); n) > 0:     # read forever
   ##     for e in inotify_events(evs[0].addr, n): echo e[].len # echo name lens
+  ##   ```
   var ev: ptr InotifyEvent = cast[ptr InotifyEvent](evs)
   var n = n
   while n > 0:

lib/posix/posix.nim

@@ -1093,11 +1093,11 @@ template onSignal*(signals: varargs[cint], body: untyped) =
   ## scope.
   ##
   ## Example:
-  ##
-  ## .. code-block::
+  ##   ```Nim
   ##   from std/posix import SIGINT, SIGTERM, onSignal
   ##   onSignal(SIGINT, SIGTERM):
   ##     echo "bye from signal ", sig
+  ##   ```
 
   for s in signals:
     handle_signal(s,