release-notes: update for 0.18.3

Author: Crypt-iQ

docs/release-notes/release-notes-0.18.3.md

@@ -76,6 +76,9 @@
   All units are `sats/kvB`. If the new field `min_relay_feerate` is not set,
   the default floor feerate (1012 sats/kvB) will be used.
 
+* Commitment fees are now taken into account when [calculating the fee
+  exposure threshold](https://github.com/lightningnetwork/lnd/pull/8824).
+
 ## RPC Updates
 
 * [`xImportMissionControl`](https://github.com/lightningnetwork/lnd/pull/8779) 
@@ -147,6 +150,7 @@
 * Andras Banki-Horvath
 * Bufo
 * Elle Mouton
+* Eugene Siegel
 * Matheus Degiovani
 * Oliver Gugger
 * Slyghtning