autogluon.multimodal vulnerable to unsafe YAML deserialization

Summary

### Impact A potential unsafe deserialization issue exists within the `autogluon.multimodal` module, where YAML files are loaded via `yaml.load()` instead of `yaml.safe_load()`. The deserialization of untrusted data may allow an unprivileged third party to cause remote code execution, denial of service, and impact to both confidentiality and integrity. Impacted versions: `>=0.4.0;<0.4.3`, `>=0.5.0;<0.5.2`. ### Patches The patches are included in `autogluon.multimodal==0.4.3`, `autogluon.multimodal==0.5.2` and Deep Learning Containers `0.4.3` and `0.5.2`. ### Workarounds Do not load data which originated from an untrusted source, or that could have been tampered with. **Only load data you trust.** ### References * https://cwe.mitre.org/data/definitions/502.html * https://www.cvedetails.com/cve/CVE-2017-18342/