build: cleanup unused dependencies (#23839)

Cleans up unused dependencies.

(cherry picked from commit f8e28cb)

package.json

@@ -140,8 +140,7 @@
     "@material/touch-target": "14.0.0-canary.1af7c1c4a.0",
     "@material/typography": "14.0.0-canary.1af7c1c4a.0",
     "@octokit/rest": "18.3.5",
-    "@rollup/plugin-babel": "^5.3.0",
-    "@rollup/plugin-commonjs": "^20.0.0",
+    "@rollup/plugin-commonjs": "^21.0.0",
     "@rollup/plugin-node-resolve": "^13.0.5",
     "@schematics/angular": "13.0.0-rc.3",
     "@types/babel__core": "^7.1.16",
@@ -152,7 +151,6 @@
     "@types/jasmine": "^3.6.0",
     "@types/luxon": "^1.27.0",
     "@types/marked": "^2.0.0",
-    "@types/merge2": "^0.3.30",
     "@types/minimist": "^1.2.0",
     "@types/node": "^14.14.22",
     "@types/node-fetch": "^2.5.5",
@@ -168,11 +166,9 @@
     "browser-sync": "2.26.13",
     "chalk": "^4.1.0",
     "codelyzer": "^6.0.2",
-    "conventional-changelog": "^3.0.5",
     "date-fns": "^2.23.0",
     "dgeni": "^0.4.11",
     "dgeni-packages": "^0.28.4",
-    "diff": "^5.0.0",
     "esbuild": "^0.13.3",
     "firebase-tools": "^9.2.1",
     "fs-extra": "^9.0.1",
@@ -196,7 +192,6 @@
     "luxon": "^2.0.0",
     "madge": "^4.0.0",
     "marked": "^2.0.0",
-    "merge2": "^1.2.3",
     "minimatch": "^3.0.4",
     "minimist": "^1.2.0",
     "moment": "^2.18.1",