CI: multi-arch-test-build: support apk in artifacts

Add support for .apk in Generate metadata step and upload built .apk
files in Store packages step.

Signed-off-by: Peter van Dijk <peter@7bits.nl>
[ improve commit title and description ]
Link: #26
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>

Author: Habbie

.github/workflows/multi-arch-test-build.yml

@@ -154,6 +154,7 @@ jobs:
           echo >> PKG-INFO
           echo Full file listing: >> PKG-INFO
           ls -al *.ipk >> PKG-INFO || true
+          ls -al *.apk >> PKG-INFO || true
           cat PKG-INFO
 
       - name: Store packages
@@ -165,6 +166,8 @@ jobs:
             Packages
             Packages.*
             *.ipk
+            packages.adb
+            *.apk
             PKG-INFO
 
       - name: Store logs