chore: Update editor script

Co-authored-by: Alois Klink <alois@aloisklink.com>

scripts/editor.bash

@@ -1,17 +1,18 @@
 #!/usr/bin/env bash
 
+set -euxo pipefail
 # We have to use npm instead of yarn because it causes trouble in netlify
 
 # Link local mermaid to npm
-pushd packages/mermaid || exit
+pushd packages/mermaid
 npm link
-popd || exit
+popd
 
 # Clone the Mermaid Live Editor repository
 git clone https://github.com/mermaid-js/mermaid-live-editor.git
 
 # Change to the repository directory
-cd mermaid-live-editor || exit
+cd mermaid-live-editor
 
 # Link local mermaid to live editor
 npm link mermaid