feat: add support for Node 16 (#7707)

BREAKING CHANGE: Removes official Node 15 support which has reached it end-of-life date.

package.json

@@ -20,7 +20,7 @@
   "license": "BSD-3-Clause",
   "dependencies": {
     "@apollographql/graphql-playground-html": "1.6.29",
-    "@graphql-tools/links": "6.2.5",
+    "@graphql-tools/links": "8.2.1",
     "@graphql-tools/stitch": "6.2.4",
     "@graphql-tools/utils": "6.2.4",
     "@parse/fs-files-adapter": "1.2.1",
@@ -62,6 +62,7 @@
   },
   "devDependencies": {
     "@actions/core": "1.2.6",
+    "@apollo/client": "3.4.17",
     "@babel/cli": "7.10.0",
     "@babel/core": "7.10.0",
     "@babel/plugin-proposal-object-rest-spread": "7.10.0",
@@ -75,12 +76,7 @@
     "@semantic-release/npm": "7.1.3",
     "@semantic-release/release-notes-generator": "9.0.3",
     "all-node-versions": "8.0.0",
-    "apollo-cache-inmemory": "1.6.6",
-    "apollo-client": "2.6.10",
-    "apollo-link": "1.2.14",
-    "apollo-link-http": "1.5.17",
-    "apollo-link-ws": "1.0.20",
-    "apollo-upload-client": "13.0.0",
+    "apollo-upload-client": "16.0.0",
     "apollo-utilities": "1.3.4",
     "babel-eslint": "10.1.0",
     "bcrypt-nodejs": "0.0.3",