Fix a few misuses of :option: I missed in r86521.

Extract of the commit message:

  Fix usage of :option: in the docs (#9312).

  :option: is used to create a link to an option of python, not to mark
  up any instance of any arbitrary command-line option.  These were
  changed to ````.
diff --git a/Doc/c-api/intro.rst b/Doc/c-api/intro.rst
index 83b98f9..843707d 100644
--- a/Doc/c-api/intro.rst
+++ b/Doc/c-api/intro.rst
@@ -588,8 +588,8 @@
 
 Compiling the interpreter with the :c:macro:`Py_DEBUG` macro defined produces
 what is generally meant by "a debug build" of Python. :c:macro:`Py_DEBUG` is
-enabled in the Unix build by adding :option:`--with-pydebug` to the
-:file:`configure` command.  It is also implied by the presence of the
+enabled in the Unix build by adding ``--with-pydebug`` to the
+:file:`./configure` command.  It is also implied by the presence of the
 not-Python-specific :c:macro:`_DEBUG` macro.  When :c:macro:`Py_DEBUG` is enabled
 in the Unix build, compiler optimization is disabled.