Cleanup unused dependencies

[jiacai2050]

Describe This Problem

There are some unused dependencies in our Cargo.toml as pointed out in #701.

Proposal

• Cleanup those unused dependencies
• Add CI to ensure this.

Additional Context

https://github.com/est31/cargo-udeps

This is what I get when run this tool against CeresDB

unused dependencies:
`benchmarks v1.0.0 (/Users/jiacai/code/misc/CeresDB/benchmarks)`
└─── dependencies
     └─── "pprof"
`cluster v1.0.0 (/Users/jiacai/code/misc/CeresDB/cluster)`
└─── dependencies
     └─── "rust-fsm"
`logger v1.0.0 (/Users/jiacai/code/misc/CeresDB/components/logger)`
└─── dependencies
     └─── "slog_derive"
`meta_client v1.0.0 (/Users/jiacai/code/misc/CeresDB/meta_client)`
└─── dependencies
     └─── "reqwest"
`parquet_ext v1.0.0 (/Users/jiacai/code/misc/CeresDB/components/parquet_ext)`
└─── dependencies
     ├─── "lru"
     └─── "parquet-format"
`profile v1.0.0 (/Users/jiacai/code/misc/CeresDB/components/profile)`
└─── dependencies
     └─── "tempfile"
`remote_engine_client v1.0.0 (/Users/jiacai/code/misc/CeresDB/remote_engine_client)`
└─── dependencies
     └─── "clru"
`server v1.0.0 (/Users/jiacai/code/misc/CeresDB/server)`
└─── dependencies
     ├─── "analytic_engine"
     └─── "system_catalog"
`tools v1.0.0 (/Users/jiacai/code/misc/CeresDB/tools)`
└─── dependencies
     └─── "env_logger"
Note: These dependencies might be used by other targets.
      To find dependencies that are not used by any target, enable `--all-targets`.
Note: They might be false-positive.
      For example, `cargo-udeps` cannot detect usage of crates that are only used in doc-tests.
      To ignore some dependencies, write `package.metadata.cargo-udeps.ignore` in Cargo.toml.

[ShiKaiWi]

Maybe we can add such a check in github workflows.

[ShiKaiWi]

cargo-udeps may lead to a very slow ci, so let's do it manually.