CI: create Github workflow to install dependencies

Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>

.github/actions/install-dependencies/action.yml

@@ -0,0 +1,12 @@
+name: 'Install dependencies'
+description: 'Install dependencies to build shadow-utils'
+runs:
+  using: "composite"
+  steps:
+  - shell: bash
+    run: |
+      sudo apt-get update -y
+      sudo apt-get install -y ubuntu-dev-tools
+      sudo sed -Ei 's/^# deb-src /deb-src /' /etc/apt/sources.list
+      sudo apt-get update -y
+      sudo apt-get -y build-dep shadow