* fix: Serialize FrontendOptions to toml
* fix: Serialize DatanodeOptions to toml
* fix: Serialize StandaloneOptions to toml
See https://users.rust-lang.org/t/why-toml-to-string-get-error-valueaftertable/85903/2
* chore!: Rename MetaClientOpts to MetaClientOptions
BREAKING CHANGE: Change the meta_client_opts in the config file to
meta_client_options