Remove short interval example

At least this should prevent a blind copy and paste leading to issues such as #1364

Author: ammgws

doc/blocks.md

@@ -1976,7 +1976,6 @@ NOTE: Some users report issues (e.g. [here](https://github.com/greshake/i3status
 block = "xrandr"
 icons = true
 resolution = true
-interval = 2
 ```
 
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