Update G2P config syntax

autokara/g2p/mappings/langs/rji/config.yaml → autokara/g2p/mappings/langs/rji/config-g2p.yaml

 <<: &shared
-  - language_name: Romaji
+  language_name: Romaji
 mappings:
   - display_name: Romaji (Hepburn) to English Arpabet
     in_lang: rji
@@ -7,8 +7,8 @@ mappings:
     authors:
       - Loïc Allègre
     type: mapping
-    mapping: romaji_to_eng-arpa.csv
-    abbreviations: rji_abbs.csv
+    rules_path: romaji_to_eng-arpa.csv
+    abbreviations_path: rji_abbs.csv
     rule_ordering: as-written
     case_sensitive: false
     norm_form: 'NFC'