chore: Enable shellcheck in prek (pre-commit) (#155)

### Summary

Enables shellcheck linter in prek and fixes current issues. 



<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- New Features
  - None.

- Bug Fixes
- Improved reliability of shell scripts by quoting variables to prevent
word splitting and globbing.
- Documentation build now correctly forwards user-supplied arguments and
handles paths with spaces.
- Superset initialisation scripts handle special characters and spaces
in credentials and database names.

- Chores
- Added a ShellCheck pre-commit hook to automatically lint shell scripts
and prevent common errors.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: martyngigg

.pre-commit-config.yaml

@@ -16,3 +16,7 @@ repos:
       # Run the formatter.
       - id: ruff-format
         files: elt-common
+  - repo: https://github.com/koalaman/shellcheck-precommit
+    rev: v0.11.0
+    hooks:
+      - id: shellcheck

docs/build.sh

@@ -22,13 +22,13 @@ DEFAULT_BUILD_ARGS="--clean"
 build_dir=$1
 shift 1
 project_root=$SCRIPT_DIR
-user_build_args=$*
+user_build_args=("$@")
 
 # Create and configure environment
-pushd $project_root
+pushd "$project_root"
 uv venv $VENV_DIR
 uv pip install -r requirements.txt
 
 # Build
-uv run mkdocs build $DEFAULT_BUILD_ARGS --site-dir $build_dir
+uv run mkdocs build $DEFAULT_BUILD_ARGS "${user_build_args[@]}" --site-dir "$build_dir"
 popd

infra/ansible-docker/roles/superset/templates/docker/docker-init.sh.j2

@@ -43,25 +43,17 @@ echo_step "1" "Starting" "Applying DB migrations"
 superset db upgrade
 echo_step "1" "Complete" "Applying DB migrations"
 
-# Create an admin user
-{# echo_step "2" "Starting" "Setting up admin user admin "
-superset fab create-admin \
-              --username $SUPERSET_ADMIN_USER \
-              --firstname $SUPERSET_ADMIN_FIRSTNAME \
-              --lastname $SUPERSET_ADMIN_LASTNAME \
-              --email $SUPERSET_ADMIN_EMAIL \
-              --password $SUPERSET_ADMIN_PASSWORD
-echo_step "2" "Complete" "Setting up admin user" #}
-
 # Create default roles and permissions
 echo_step "2" "Starting" "Setting up roles and perms"
 superset init
 echo_step "2" "Complete" "Setting up roles and perms"
 
 # Create a database connection(s)
 echo_step "3" "Starting" "Setting up Iceberg catalog connection(s)"
+# shellcheck disable=1000-9999
 {% for analytic_db in superset_analytic_dbs %}
   superset set-database-uri \
     --database_name {{ analytic_db.database_name }} --uri "{{ analytic_db.uri }}"
+# shellcheck disable=1000-9999
 {% endfor %}
 echo_step "3" "Complete" "Setting up data source database connection(s)"

infra/local/superset/docker/docker-init.sh

@@ -46,11 +46,11 @@ echo_step "1" "Complete" "Applying DB migrations"
 # Create an admin user
 echo_step "2" "Starting" "Setting up admin user admin "
 superset fab create-admin \
-              --username $SUPERSET_ADMIN_USER \
-              --firstname $SUPERSET_ADMIN_FIRSTNAME \
-              --lastname $SUPERSET_ADMIN_LASTNAME \
-              --email $SUPERSET_ADMIN_EMAIL \
-              --password $SUPERSET_ADMIN_PASSWORD
+              --username "$SUPERSET_ADMIN_USER" \
+              --firstname "$SUPERSET_ADMIN_FIRSTNAME" \
+              --lastname "$SUPERSET_ADMIN_LASTNAME" \
+              --email "$SUPERSET_ADMIN_EMAIL" \
+              --password "$SUPERSET_ADMIN_PASSWORD"
 echo_step "2" "Complete" "Setting up admin user"
 
 # Create default roles and permissions
@@ -61,6 +61,6 @@ echo_step "3" "Complete" "Setting up roles and perms"
 # Create a database connection
 echo_step "4" "Starting" "Setting up Iceberg catalog connection"
 superset set-database-uri \
-  --database_name $SUPERSET_DB_SCHEMA_NAME \
+  --database_name "$SUPERSET_DB_SCHEMA_NAME" \
   --uri "trino://trino@trino:8080/$SUPERSET_DB_SCHEMA_NAME"
 echo_step "4" "Complete" "Setting up data source database connection"