meta: add installing dependencies for build process

.gitlab-ci.yml

@@ -2,6 +2,7 @@ build:
   stage: build
   image: alpine:3.13
   script:
+    - apk add bash abuild
     - ./build.sh
   rules:
     - if: '$CI_COMMIT_BRANCH == "master"'

build.sh

@@ -1,4 +1,6 @@
-#!/bin/sh
+#!/bin/bash
+
+set -euxo pipefail
 
 for pkg in packages/*; do
 	cd $pkg