Switch to using diff-cover for the Coverage gate (#33673)

* Switch to using diff-cover for the Coverage gate

Enabling developers to check their PR coverage without waiting for CI

* Remove sonar-project.properties - in automatic mode Sonar will not read this file

* Add note to CONTRIBUTING.md

* Skip sonar in MQ

packages/shared-components/package.json

@@ -51,6 +51,8 @@
         "test:unit": "nx test:unit",
         "test:storybook": "nx test:storybook",
         "test:storybook:update": "nx test:storybook:update",
+        "coverage": "pnpm test:unit --coverage",
+        "coverage:diff": "diff-cover --config-file ../../diff-cover.toml coverage/lcov.info",
         "build": "nx build",
         "prepack": "pnpm run build",
         "storybook": "storybook dev -p 6007",
@@ -132,8 +134,7 @@
         "unplugin-dts": "1.0.1",
         "vite": "catalog:",
         "vite-plugin-node-polyfills": "^0.28.0",
-        "vitest": "catalog:",
-        "vitest-sonar-reporter": "catalog:"
+        "vitest": "catalog:"
     },
     "engines": {
         "node": ">=20.0.0"