Fix typos (#13520)

Author: hugovk

doc/man/sphinx-build.rst

@@ -272,13 +272,13 @@ Options
    From Sphinx 8.1, :option:`!--keep-going` is always enabled.
    Previously, it was only applicable whilst using :option:`--fail-on-warning`,
    which by default exited :program:`sphinx-build` on the first warning.
-   Using :option:`!--keep-going` runs :program:`!sphinx-build` to completion
+   Using :option:`!--keep-going` runs :program:`sphinx-build` to completion
    and exits with exit status 1 if errors are encountered.
 
    .. versionadded:: 1.8
    .. versionchanged:: 8.1
       :program:`sphinx-build` no longer exits on the first warning,
-      meaning that in effect :option:`!--fail-on-warning` is always enabled.
+      meaning that in effect :option:`!--keep-going` is always enabled.
       The option is retained for compatibility, but may be removed at some
       later date.