Use pmatch instead of fd.directory

Use pmatch, which compares a file against a set of prefix paths, instead
of fd.directory. This allows the directories in safe_etc_dirs to be a
prefix of a file instead of just the directory containing a file.

rules/falco_rules.yaml

@@ -394,7 +394,7 @@
                           gen_resolvconf., update-ca-certi, certbot, runsv,
                           qualys-cloud-ag)
     and not proc.pname in (sysdigcloud_binaries, sendmail_config_binaries)
-    and not fd.directory in (safe_etc_dirs)
+    and not fd.name pmatch (safe_etc_dirs)
     and not fd.name in (/etc/container_environment.sh, /etc/container_environment.json)
     and not ansible_running_python
     and not python_running_denyhosts