Fixes incorrect error description

The OutOfMemory error must be removed from popen.new and popen.read. No versioning required because it was never returned at all for the mentioned functions.
Fixes#3608

Author: AArdeev

doc/reference/reference_lua/popen.rst

@@ -165,20 +165,19 @@ Below is a list of all ``popen`` functions and handle methods.
 
              (if failure) ``nil, err``
 
-    Possible raised errors are:
+    Possible raised errors:
 
-    * IllegalParams: incorrect type or value of a parameter
-    * IllegalParams: group signal is set, while setsid is not
+    * ``IllegalParams``: incorrect type or value of a parameter
+    * ``IllegalParams``: group signal is set, while setsid is not
 
-    Possible error reasons when ``nil, err`` is returned are:
+    Possible error reasons when ``nil, err`` is returned:
 
-    * SystemError: dup(), fcntl(), pipe(), vfork() or close() fails in the
+    * ``SystemError``: dup(), fcntl(), pipe(), vfork() or close() fails in the
       parent process
-    * SystemError: (temporary restriction) the parent process has closed stdin,
+    * ``SystemError``: (temporary restriction) the parent process has closed stdin,
       stdout or stderr
-    * OutOfMemory: unable to allocate the handle or a temporary buffer
 
-    Possible ``opts`` items are:
+    Possible ``opts`` items:
 
     * ``opts.stdin`` (action on STDIN_FILENO)
     * ``opts.stdout`` (action on STDOUT_FILENO)
@@ -397,7 +396,7 @@ Below is a list of all ``popen`` functions and handle methods.
                           :ref:`popen.shell() <popen-shell>`
         :param table opts: options
 
-        Possible ``opts`` items are:
+        Possible ``opts`` items:
 
         * ``opts.stdout`` (boolean, default ``true``, if ``true`` then read from stdout)
         * ``opts.stderr`` (boolean, default ``false``, if ``true`` then read from stderr)
@@ -415,19 +414,18 @@ Below is a list of all ``popen`` functions and handle methods.
 
         These errors are raised on incorrect parameters or when the fiber is cancelled:
 
-        * IllegalParams:    incorrect type or value of a parameter
-        * IllegalParams:    called on a closed handle
-        * IllegalParams:    opts.stdout and opts.stderr are both set
-        * IllegalParams:    a requested IO operation is not supported by
+        * ``IllegalParams``:    incorrect type or value of a parameter
+        * ``IllegalParams``:    called on a closed handle
+        * ``IllegalParams``:    opts.stdout and opts.stderr are both set
+        * ``IllegalParams``:    a requested IO operation is not supported by
           the handle (stdout / stderr is not piped)
-        * IllegalParams:    attempt to operate on a closed file descriptor
-        * FiberIsCancelled: cancelled by external code
+        * ``IllegalParams``:    attempt to operate on a closed file descriptor
+        * ``FiberIsCancelled``: cancelled by external code
 
         ``nil, err`` is returned on following failures:
 
         * SocketError: an IO error occurs at read()
         * TimedOut:    exceeded the opts.timeout quota
-        * OutOfMemory: no memory space for a buffer to read into
         * LuajitError: ("not enough memory"): no memory space for the Lua string
 
     ..  _popen-write: