r/fluent-bit: Support configuring parsers

When ingesting logs from sources other than systemd, such as
unstructured log files written by uncooperative services, it may be
necessary to define custom parsers.

roles/fluent-bit/defaults/main.yml

@@ -1,5 +1,7 @@
 fluent_bit_config:
   service: '{{ fluent_bit_config_service }}'
+  parsers: '{{ fluent_bit_parsers }}'
+  multiline_parsers: '{{ fluent_bit_multiline_parsers }}'
   pipeline: '{{ fluent_bit_pipeline }}'
 
 fluent_bit_config_service:
@@ -24,6 +26,10 @@ fluent_bit_input_systemd:
   lowercase: true
   strip_underscores: true
 
+fluent_bit_parsers: []
+
+fluent_bit_multiline_parsers: []
+
 fluent_bit_filters: []
 
 fluent_bit_outputs: