Update nightly build release notes

Adds note about untainting MacOS binary.

.github/workflows/nightly-build.yml

@@ -43,6 +43,10 @@ jobs:
                   artifacts/*
                 body: |
                   ${{ steps.notes.outputs.notes }}
+
+                  ### MacOS builds
+
+                  MacOS builds are not signed, so you will need to run ```xcattr -cr /path/to/your/INAV Configurator.app``` from the command line to remove the warnings about it being a downloaded application or moving it to trash when trying to launch.
       
                   ### Repository:
                   ${{ github.repository }} ([link](${{ github.event.repository.html_url }}))
@@ -55,4 +59,4 @@ jobs:
 
                   ### Changes:
                   ${{ github.event.head_commit.message }}
-
+