cleanup: remove startswith /etc

In macro `sensitive_files` the `startswith /etc` is redundant because it
used in combination with the `in` condition

Signed-off-by: Andrea Terzolo <andreaterzolo3@gmail.com>

rules/falco_rules.yaml

@@ -208,7 +208,7 @@
 
 - macro: sensitive_files
   condition: >
-    ((fd.name startswith /etc and fd.name in (sensitive_file_names)) or
+    (fd.name in (sensitive_file_names) or
       fd.directory in (/etc/sudoers.d, /etc/pam.d))
 
 # Indicates that the process is new. Currently detected using time