es-grammars: fix build issue (?)

Author: pdubroy

packages/es-grammars/package.json

@@ -8,7 +8,7 @@
     "gen/*.ohm"
   ],
   "scripts": {
-    "build": "for year in {2015..2022}; do YEAR=$year pnpm run gen-grammar; done",
+    "build": "for year in $(seq 2015 2022); do YEAR=$year npm run gen-grammar; done",
     "test": "node test/es2015.test.mjs",
     "gen-grammar": "node scripts/generate-ecmascript-grammar.mjs --verbose --name ES$YEAR --overrides spec/es$YEAR/overrides.json spec/es$YEAR/spec.grammar > gen/es$YEAR.grammar.ohm",
     "gen-grammar:es2015": "YEAR=2015 pnpm run gen-grammar"