nit: descendent should be spelled descendant even in the release-notes

Author: mryandao

doc/release-notes.md

@@ -72,8 +72,8 @@ RPC changes
   `getrawtransaction` RPC commands.
 - New `fees` field introduced in `getrawmempool`, `getmempoolancestors`, `getmempooldescendants` and
    `getmempoolentry` when verbosity is set to `true` with sub-fields `ancestor`, `base`, `modified`
-   and `descendent` denominated in BTC. This new field deprecates previous fee fields, such as
-   `fee`, `modifiedfee`, `ancestorfee` and `descendentfee`.
+   and `descendant` denominated in BTC. This new field deprecates previous fee fields, such as
+   `fee`, `modifiedfee`, `ancestorfee` and `descendantfee`.
 
 External wallet files
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