refactor: don't use JS if it's a simple key/value topic (#609)

Author: mfranzke

.config/.lintstagedrc-prettier.js

@@ -0,0 +1 @@
+{ "**/*": "prettier --write --ignore-unknown" }

.config/.lintstagedrc-prettier.json

@@ -1,9 +1,9 @@
 echo "### validate branch name ###"
 validate-branch-name
 echo "### lint staged files ###"
-lint-staged
+lint-staged --config .config/.lintstagedrc.json
 echo "### prettify staged files ###"
-lint-staged --config .config/.lintstagedrc-prettier.js
+lint-staged --config .config/.lintstagedrc-prettier.json
 git update-index --again
 echo "### check for commit mail ###"
 node ./scripts/check-commit-mail.mjs