Upgrade eslint-plugin-flowtype to the latest version 5.7.1

This release includes some fixes for our codebase, see:

- gajus/eslint-plugin-flowtype#477
- gajus/eslint-plugin-flowtype#478

adeira-source-id: a16fb4f4e7da1a952452a75cb4c4cc58f92e69bf

package.json

@@ -12,7 +12,7 @@
     "eslint-config-prettier": "^8.2.0",
     "eslint-plugin-adeira": "^0.13.0",
     "eslint-plugin-eslint-comments": "^3.2.0",
-    "eslint-plugin-flowtype": "^5.7.0",
+    "eslint-plugin-flowtype": "^5.7.1",
     "eslint-plugin-import": "^2.22.1",
     "eslint-plugin-jest": "^24.3.5",
     "eslint-plugin-jsx-a11y": "^6.4.1",