Missing org config repo causes failures

### TL;DR

A continuation of https://github.com/abcxyz/github-token-minter/issues/205 as the fix did not seem to fully fix the issue:

```
"error reading configuration for repository *** from configuration store with config_source https://github.com/***/.minty/minty.yaml: error reading configuration, child reader threw error: failed to load configuration file for [***]. Error: compiling config loader, sub loader failed to load configuration: error reading config file from child loader: error reading configuration file contents @ ***/.minty/minty.yaml: error minting access token for GitHub: errors retrieving GitHub installation: failed to get access token url for repo ***/.minty: invalid http response status (expected 404 to be 200): {"message":"Not Found","documentation_url":"https://docs.github.com/rest/apps/apps#get-a-repository-installation-for-the-authenticated-app","status":"404"}"
```

Filing a new bug to have something to refer to :)

### Expected behavior

_No response_

### Observed behavior

_No response_

### Environment Details

```markdown
v2.3.2
```

### Additional information

_No response_