build(deps): remove rollup-plugin-terser, replace with @rollup/plugin-terser

Removing deprecated rollup-plugin-terser package. Replaced with @rollup/plugin-terser

Author: Aetherinox

package-lock.json

@@ -28,6 +28,7 @@
   "devDependencies": {
     "@rollup/plugin-commonjs": "^18.0.0",
     "@rollup/plugin-node-resolve": "^11.2.1",
+    "@rollup/plugin-terser": "^0.4.4",
     "@rollup/plugin-typescript": "^8.2.1",
     "@types/node": "^14.14.37",
     "obsidian": "^1.0.0",