chore(ci): more action updates

Some bumps missed in missed in a4e3275ef3

.github/workflows/build_fw.yml

@@ -148,7 +148,7 @@ jobs:
         run: echo "artifact_name=edgetx-firmware-${GITHUB_REF##*/}" >> $GITHUB_ENV
 
       - name: Merge firmware artifact packages
-        uses: actions/upload-artifact/merge@v4
+        uses: actions/upload-artifact/merge@v7
         with:
           name: "${{ env.artifact_name }}"
           pattern: firmware-*

.github/workflows/macosx_cpn.yml

@@ -43,7 +43,7 @@ jobs:
           submodules: recursive
 
       - name: Setup Python 3.12
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: '3.12'
 

.github/workflows/nightly.yml

@@ -81,7 +81,7 @@ jobs:
           fetch-depth: 0  # Need full history for changelog
 
       - name: Download artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           pattern: edgetx-firmware-nightly-*
           path: edgetx-firmware-nightly