Clean up extra spaces

Clean up extra spaces, although these errors are not important, they affect the code specification.

Signed-off-by: jayonlau <[email protected]>

Author: jayonlau

Diff for: example/v0_12_filter.conf

@@ -52,10 +52,10 @@
 </match>
 
 # Composing two filters. For all events with the tag foo.bar,
-# 
+#
 # 1. The first filter filters out all events that has the field "hello"
 # 2. Then, for those events, we downcase the value of the "name" field.
-# 
+#
 # - {"name":"SADA", "hello":100} gets filtered out
 # - {"name":"SADA"} becomes {"name":"sada"}
 # - {"last_name":"FURUHASHI"} throws an error because it has no field called "name"