fix(Controller): Errors are hidden by default

[jokemanfire]

I don't think errors should be hidden here, it will cause the error to occur in the subsequent process, and I think this design is incorrect.
you can choose to ignore this error ,but should not hide it in inner.

  let cg = Cgroup::new(hierarchies::auto(), path).unwrap();
  let mem_controller: &MemController = cg.controller_of().unwrap();
  mem_controller.set_limit(10 * 1024 * 1024).unwrap(); // 10M

this will case the panic occur in set_limit,this is unreasonable.

[Tim-Zhang]

LGTM, thanks @jokemanfire

[justxuewei]

Why add a <'_> here?

[jokemanfire]

when I usemake check rustc 1.90 clippy put out this warning.

[jokemanfire]

error: could not compile cgroups-rs (lib) due to 1 previous error
warning: build failed, waiting for other jobs to finish...
error: hiding a lifetime that's elided elsewhere is confusing
--> src/systemd/dbus/client.rs:251:51
|
251 | fn start_default_cgroup(pid: CgroupPid, unit: &str) -> SystemdClient {
| ^^^^ ------------- the same lifetime is hidden here
| |
| the lifetime is elided here
|
= help: the same lifetime is referred to in inconsistent ways, making the signature confusing
= note: -D mismatched-lifetime-syntaxes implied by -D warnings
= help: to override -D warnings add #[allow(mismatched_lifetime_syntaxes)]
help: use '_ for type paths
|
251 | fn start_default_cgroup(pid: CgroupPid, unit: &str) -> SystemdClient<'_> {

[justxuewei]

Lgtm, thanks!