Update composer.json description to be more descriptive (#10)

* Initial plan

* Update composer.json description to be more descriptive

Co-authored-by: jahidulpabelislam <15434150+jahidulpabelislam@users.noreply.github.com>

* Shorten description and remove redundant 'PHP' mention

Co-authored-by: jahidulpabelislam <15434150+jahidulpabelislam@users.noreply.github.com>

* Shorten description in composer.json

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: jahidulpabelislam <15434150+jahidulpabelislam@users.noreply.github.com>
Co-authored-by: Jahidul Pabel Islam <jahidul.pabel.islam@hotmail.com>

Author: Copilot

composer.json

@@ -1,6 +1,6 @@
 {
     "name": "jpi/cron-linter",
-    "description": "Cron Linting Tool",
+    "description": "Tool for linting cron files and expressions",
     "license": "GPL-3.0-only",
     "type": "library",
     "authors": [