RepoConfig and SqlRegistryConfig may leak secrets

Still very new to feast, but noticed playing around with the SDK that the configs related to Sql registries dump the path in plaintext and wanted to recommend they be obfuscated.

```
>>> from feast import FeatureStore
>>> fs = FeatureStore(".")
>>> fs
FeatureStore(
repo_path=PosixPath('.'),
config=RepoConfig(project='development', provider='gcp', registry_config={'registry_type': 'sql', 'path': 'mysql+pymysql://[REDACTED]:[REDACTED]@...' ...
```