codewide: adjust for MSRV 1.80

After the recent bump of MSRV to 1.80, several places in code went
obsolete.

Author: wprzytula

scylla/src/client/session_builder.rs

@@ -28,7 +28,6 @@ use tracing::warn;
 mod sealed {
     // This is a sealed trait - its whole purpose is to be unnameable.
     // This means we need to disable the check.
-    #[allow(unknown_lints)] // Rust 1.66 doesn't know this lint
     #[allow(unnameable_types)]
     pub trait Sealed {}
 }

scylla/src/network/tls.rs

@@ -83,9 +83,7 @@ impl TlsProvider {
                 };
 
                 cloud_config.make_tls_config_for_scylla_cloud_host(host_id, dc, address)
-                    // inspect_err() is stable since 1.76.
-                    // TODO: use inspect_err once we bump MSRV to at least 1.76.
-                    .map_err(|err| {
+                    .inspect_err(|err| {
                         warn!(
                             "TlsProvider for SNI connection to Scylla Cloud node {{ host_id={:?}, dc={:?} at {} }} could not be set up: {}\n Proceeding with attempting probably nonworking connection",
                             host_id,

scylla/src/routing/partitioner.rs

@@ -78,7 +78,6 @@ impl PartitionerHasher for PartitionerHasherAny {
 mod sealed {
     // This is a sealed trait - its whole purpose is to be unnameable.
     // This means we need to disable the check.
-    #[allow(unknown_lints)] // Rust 1.70 doesn't know this lint
     #[allow(unnameable_types)]
     pub trait Sealed {}
 }