chore: update documentation URLs to use workspace setting

Replace all docs.rs documentation URLs with documentation.workspace = true
to inherit from the workspace's docs.pezkuwichain.io URL.

pezkuwi/pezpallets/validator-pool/Cargo.toml

@@ -8,7 +8,7 @@ edition.workspace = true
 license.workspace = true
 publish = false
 repository.workspace = true
-documentation = "https://docs.rs/pezpallet-validator-pool"
+documentation.workspace = true
 
 [package.metadata.docs.rs]
 targets = ["x86_64-unknown-linux-gnu"]