package.json: use "npm exec" for running the "concurrently" tool

Signed-off-by: Maël Valais <mael@vls.dev>

package.json

@@ -22,7 +22,7 @@
     "generate:sitemap": "next-sitemap",
     "export": "next export",
     "start": "next start",
-    "check": "concurrently --group --timings npm:check:* # Run all the npm check:* scripts in parallel",
+    "check": "npm exec concurrently -y -- --group --timings npm:check:* # Run all the npm check:* scripts in parallel",
     "check:next-lint": "next lint",
     "check:links": "find content/docs -type f -name '*.md' | xargs markdown-link-check --quiet --config markdown-link-check.json 2>&1 | awk -v RS=FILE: '/ERROR/{f=1; print RS $0} END{exit f}' # Split into records based on the word FILE and print only records containing word ERROR",
     "check:spelling": "FORCE_COLOR=1 mdspell --report --en-us --ignore-numbers --ignore-acronyms 'content/**/*.md' 'content/**/*.html' '_layouts/*.html' '_includes/*.html' '*.html' '!**/api-docs.md' # Force color output in mdspell. # See https://github.com/lukeapage/node-markdown-spellcheck/issues/36#issuecomment-482649408 ",