org-manual: Fix typo

* doc/org-manual.org (Computed tag filtering): Fix spacing after
"i.e.".

doc/org-manual.org

@@ -9194,8 +9194,8 @@ the Internet, and outside of business hours, with something like this:
 #+end_src
 
 You can apply this self-adapting filter by using a triple prefix
-argument to ~org-agenda-filter~, i.e. press {{{kbd(C-u C-u C-u /)}}}, or
-by pressing {{{kbd(RET)}}} in ~org-agenda-filter-by-tag~.
+argument to ~org-agenda-filter~, i.e.\nbsp{}press {{{kbd(C-u C-u C-u /)}}},
+or by pressing {{{kbd(RET)}}} in ~org-agenda-filter-by-tag~.
 
 **** Setting limits for the agenda
 :PROPERTIES: