deps: bump @types/node-fetch from 2.5.5 to 2.5.6

Bumps [@types/node-fetch](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/node-fetch) from 2.5.5 to 2.5.6.
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/node-fetch)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package-lock.json

@@ -2404,9 +2404,9 @@
       "dev": true
     },
     "@types/node-fetch": {
-      "version": "2.5.5",
-      "resolved": "https://registry.npmjs.org/@types/node-fetch/-/node-fetch-2.5.5.tgz",
-      "integrity": "sha512-IWwjsyYjGw+em3xTvWVQi5MgYKbRs0du57klfTaZkv/B24AEQ/p/IopNeqIYNy3EsfHOpg8ieQSDomPcsYMHpA==",
+      "version": "2.5.6",
+      "resolved": "https://registry.npmjs.org/@types/node-fetch/-/node-fetch-2.5.6.tgz",
+      "integrity": "sha512-2w0NTwMWF1d3NJMK0Uiq2UNN8htVCyOWOD0jIPjPgC5Ph/YP4dVhs9YxxcMcuLuwAslz0dVEcZQUaqkLs3IzOQ==",
       "dev": true,
       "requires": {
         "@types/node": "*",

package.json

@@ -60,7 +60,7 @@
   "devDependencies": {
     "@types/jest": "^25.2.1",
     "@types/node": "~12",
-    "@types/node-fetch": "^2.5.5",
+    "@types/node-fetch": "^2.5.6",
     "@typescript-eslint/eslint-plugin": "^2.27.0",
     "@typescript-eslint/parser": "^2.27.0",
     "@zeit/ncc": "^0.22.1",