Update getSignaturesForAddress and getConfirmedSignaturesForAddress2 RPC call description (#21955) (#21960)

* Update jsonrpc-api.md

* Update docs/src/developing/clients/jsonrpc-api.md

Co-authored-by: Tyera Eulberg <teulberg@gmail.com>

* Wrap 80chars

* Update docs/src/developing/clients/jsonrpc-api.md

Co-authored-by: Tyera Eulberg <teulberg@gmail.com>
(cherry picked from commit 3398f5a2f5)

Co-authored-by: jdcaballerov <743513+jdcaballerov@users.noreply.github.com>

docs/src/developing/clients/jsonrpc-api.md

@@ -1971,8 +1971,9 @@ Result:
 ### getSignaturesForAddress
 
 
-Returns confirmed signatures for transactions involving an
+Returns signatures for confirmed transactions that include the given address in
-address backwards in time from the provided signature or most recent confirmed block
+their `accountKeys` list. Returns signatures backwards in time from the
+provided signature or most recent confirmed block
 
 #### Parameters:
 * `<string>` - account address as base-58 encoded string
@@ -4367,8 +4368,10 @@ Result:
 **DEPRECATED: Please use [getSignaturesForAddress](jsonrpc-api.md#getsignaturesforaddress) instead**
 This method is expected to be removed in solana-core v2.0
 
-Returns confirmed signatures for transactions involving an
+Returns signatures for confirmed transactions that include the given address in
-address backwards in time from the provided signature or most recent confirmed block
+their `accountKeys` list. Returns signatures backwards in time from the
+provided signature or most recent confirmed block
+
 
 #### Parameters:
 * `<string>` - account address as base-58 encoded string