Run apt update in Ubuntu CI

Author: tchoutri

.github/workflows/install-system-dependencies.sh

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
 case "$(uname -s)" in
-        Linux*) sudo apt install postgresql liblzma-dev;;
+        Linux*) sudo apt update && sudo apt install postgresql liblzma-dev;;
         Darwin*) brew install postgresql openssl;;
 esac