Delete pending validators

[Al3xGROS]

Changes

• delete every notion of pending validators
• fit the need of the new AvalancheGo 1.11.3 version

Additional comments

This is the v0.4.3-rc.1 tag release. When merged, we'll need to update the version of the release to 0.4.3.

[Nuttymoon]

Run cargo clippy and fix the issues.

[Al3xGROS]

Run cargo clippy and fix the issues.

I fixed most of the warnings.
However, there should be still one warning when running cargo clippy:

warning: called `unwrap` on `id_from_cb58` after checking its variant with `is_ok`
  --> crates/ash_cli/src/utils/parsing.rs:16:19
   |
15 |     if id_from_cb58.is_ok() {
   |     ----------------------- help: try: `if let Ok(..) = id_from_cb58`
16 |         return Ok(id_from_cb58.unwrap());
   |                   ^^^^^^^^^^^^^^^^^^^^^
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_unwrap
   = note: `#[warn(clippy::unnecessary_unwrap)]` on by default

But when I try to fix it by following the help indication I get:

warning: redundant pattern matching, consider using `is_ok()`
  --> crates/ash_cli/src/utils/parsing.rs:15:12
   |
15 |     if let Ok(..) = id_from_cb58 {
   |     -------^^^^^^--------------- help: try: `if id_from_cb58.is_ok()`
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#redundant_pattern_matching
   = note: `#[warn(clippy::redundant_pattern_matching)]` on by default

It's a warning that also exists on the main branch so do we need to fix it in this PR ?