Fix frame-benchmarking-cli not buildable without rocksdb

[bgallois]

Description

The frame-benchmarking-cli crate has not been buildable without the rocksdb feature since version 1.17.0.

Error:

self.database()?.unwrap_or(Database::RocksDb),
                             ^^^^^^^ variant or associated item not found in `Database`

This issue is also related to the rocksdb feature bleeding (#3793), where the rocksdb feature was always activated even when compiling this crate with --no-default-features.

Fix:

• Resolved the error by choosing paritydb as the default database when compiled without the rocksdb feature.
• Fixed the issue where the sc-cli crate's rocksdb feature was always active, even compiling frame-benchmarking-cli with --no-default-features.

Review Notes

Fix the crate to be built without rocksdb, not intended to solve #3793.

[bkchr]

/cmd prdoc --audience runtime_dev --bump patch