Migrate content syntax via script

The changes in this commit were auto-generated by running

tool/migrate.sh

Following this commit, the Dactyl build no longer works but the Redocly
build (mostly) should.

content/references/http-websocket-apis/public-api-methods/account-methods/index.md

@@ -1,8 +1,12 @@
 ---
 html: account-methods.html
 parent: public-api-methods.html
-template: pagetype-category.html.jinja
+metadata:
+  indexPage: true
 ---
 # Account Methods
 
-An account in the XRP Ledger represents a holder of XRP and a sender of transactions. Use these methods to work with account info.
+An account in the XRP Ledger represents a holder of XRP and a sender of transactions. Use these methods to work with account info.
+
+
+{% child-pages /%}