CLI call to openapi-spec with security in path fails

Type: Bug
Since: 1.8.0

Description:
The CLI call `php-openapi validate example.spec.json` fails due to the fact that the security in path is transformed to a list of arrays and not a list of objects in https://github.com/cebe/php-openapi/blob/893ab104be1f5dfe5a39766703f583584e43c6e1/src/spec/SecurityRequirements.php#L64

Minimal example.spec.json to reproduce:
```json
{
"openapi": "3.0.0",
"info": {
"title": "My API",
"version": "1, 2"
},
"paths": {
"/v1/users/profile": {
"get": {
"operationId": "V1GetUserProfile",
"summary": "Returns the user profile",
"responses": {
"200": {
"description": "dummy"
}
},
"security": [
{
"test_test": ["test:scope:foo"]
}
]
}
}
},
"components": {
"securitySchemes": {
"test_test": {
"type": "oauth2",
"flows": {
"authorizationCode": {
"authorizationUrl": "https://example.com/openid-connect/auth",
"tokenUrl": "https://example.com/openid-connect/token",
"scopes": {
"test:scope:foo": "test_scope"
}
}
}
}
}
}
}
```

I'll provide a MR with test case and a fix if you like.

Start at src/spec/SecurityRequirements.php around line 64 and reproduce the failure with the minimal example.spec.json from the issue using the php-openapi validate CLI command. Trace how the security requirement is transformed, then add the mentioned test case and verify that validation succeeds with the security entry represented correctly.

Written by the indexing model from the issue text.