fix(role): Correctly rebuild Postfix files

We were accidentally looking for Jinja2 files ending in .j2. That was
a copy-paste error, those files do not have a .j2 file extension.

handlers/main.yml

@@ -4,8 +4,8 @@
     loop_var: 'somta_postfix_postmap_handler'
     label: 'Rebuild ''/etc/postfix/{{ somta_postfix_postmap_handler.lookup_table_source_file }}'' lookup table'
   loop:
-    - { lookup_table_source_file: 'sasl_passwd.j2' }
-    - { lookup_table_source_file: 'sender_canonical_maps.j2' }
+    - { lookup_table_source_file: 'sasl_passwd' }
+    - { lookup_table_source_file: 'sender_canonical_maps' }
     - { lookup_table_source_file: 'smtp_header_checks' }
   ansible.builtin.shell: |
     postmap '/etc/postfix/{{ somta_postfix_postmap_handler.lookup_table_source_file }}'