Remove Node 18 from CI matrix

Agent-Logs-Url: https://github.com/LinkedSoftwareDependencies/Components.js/sessions/8e0506ff-ee97-4ed4-a2ce-78b005276310

Co-authored-by: rubensworks <440384+rubensworks@users.noreply.github.com>

Author: Copilot

.github/workflows/ci.yml

@@ -22,7 +22,6 @@ jobs:
       matrix:
         os: [ubuntu-latest, windows-latest, macos-latest]
         node-version:
-          - 18.x
           - 20.x
           - 22.x
           - 24.x