Cant submit PTC vote for a missed slot

## Description

Fetching payload attestation data for a missed slot errors out and we never submit a PTC for that missed slot

``` bash
Apr 29 07:18:39.002 WARN  Error processing HTTP API request             elapsed_ms: 0.7446109999999999, status: 400 Bad Request, path: /eth/v1/validator/payload_attestation_data/1549, method: GET
```
