fix(deps): update dependency conventional-changelog-angular to v6 (semantic-release#460)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

package-lock.json

@@ -17,7 +17,7 @@
     "Gregor Martynus (https://twitter.com/gr2m)"
   ],
   "dependencies": {
-    "conventional-changelog-angular": "^5.0.0",
+    "conventional-changelog-angular": "^6.0.0",
     "conventional-commits-filter": "^3.0.0",
     "conventional-commits-parser": "^4.0.0",
     "debug": "^4.0.0",