chore(deps): update dependency c8 to v7 (#838)

Co-authored-by: Benjamin E. Coe <bencoe@google.com>
Co-authored-by: Alexander Fenster <github@fenster.name>

Author: 3 people

handwritten/pubsub/package.json

@@ -76,7 +76,7 @@
     "@types/sinon": "^7.0.0",
     "@types/tmp": "^0.1.0",
     "@types/uuid": "^3.4.4",
-    "c8": "^6.0.1",
+    "c8": "^7.0.0",
     "codecov": "^3.0.0",
     "eslint": "^6.0.0",
     "eslint-config-prettier": "^6.0.0",