ulimit: fix linting (remove trailing spaces)

pages/linux/ulimit.md

@@ -6,14 +6,14 @@
 
 `ulimit -a`
 
-- get hard limit for the number of simultaneously opened files 
+- get hard limit for the number of simultaneously opened files
 
 `ulimit -H -n`
 
-- get soft limit for the number of simultaneously opened files 
+- get soft limit for the number of simultaneously opened files
 
-`ulimit -S -n` 
+`ulimit -S -n`
 
-- set max per-user process limit 
+- set max per-user process limit
 
 `ulimit -u 30`