build(yarn): add @octokit/openapi-types

avoids:

```
node_modules/@octokit/core/node_modules/@octokit/types/dist-types/generated/Endpoints.d.ts:1:23 - error TS2307: Cannot find module '@octokit/openapi-types' or its corresponding type declarations.

1 import { paths } from "@octokit/openapi-types";
                        ~~~~~~~~~~~~~~~~~~~~~~~~

Found 1 error.

error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.
```

package.json

@@ -43,6 +43,7 @@
   "version": "1.0.0",
   "devDependencies": {
     "@changesets/cli": "^2.11.0",
+    "@octokit/openapi-types": "^2.0.0",
     "@spotify/eslint-config-oss": "^1.0.1",
     "@spotify/prettier-config": "^8.0.0",
     "command-exists": "^1.2.9",

yarn.lock

@@ -3920,6 +3920,11 @@
     "@octokit/types" "^5.0.0"
     universal-user-agent "^6.0.0"
 
+"@octokit/openapi-types@^2.0.0":
+  version "2.0.0"
+  resolved "https://registry.npmjs.org/@octokit/openapi-types/-/openapi-types-2.0.0.tgz#6d8f8ad9db3b75a39115f5def2654df8bed39f28"
+  integrity sha512-J4bfM7lf8oZvEAdpS71oTvC1ofKxfEZgU5vKVwzZKi4QPiL82udjpseJwxPid9Pu2FNmyRQOX4iEj6W1iOSnPw==
+
 "@octokit/plugin-enterprise-rest@^6.0.1":
   version "6.0.1"
   resolved "https://registry.npmjs.org/@octokit/plugin-enterprise-rest/-/plugin-enterprise-rest-6.0.1.tgz#e07896739618dab8da7d4077c658003775f95437"