Add Clone to HickoryDnsResolver and TokioDnsResolver (#4289)

## Description
<!--- Describe your changes in detail -->
The `HickoryDnsResolver` and `TokioDnsResolver` were not `Clone` making
it impossible to use them in the http_client builder's
`build_with_resolver` method.

## Checklist
<!--- If a checkbox below is not applicable, then please DELETE it
rather than leaving it unchecked -->
- [x] For changes to the smithy-rs codegen or runtime crates, I have
created a changelog entry Markdown file in the `.changelog` directory,
specifying "client," "server," or both in the `applies_to` key.


----

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copy, and redistribute this contribution, under the terms of your
choice._

Author: landonxjames

.changelog/dns-clone.md

@@ -0,0 +1,9 @@
+---
+applies_to: ["client"]
+authors: ["landonxjames"]
+references: ["smithy-rs#4274"]
+breaking: false
+new_feature: false
+bug_fix: true
+---
+The `HickoryDnsResolver` and `TokioDnsResolver` were not `Clone` making it impossible to use them in the http_client builder's `build_with_resolver` method.

rust-runtime/Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "aws-smithy-dns"
-version = "0.1.0"
+version = "0.1.1"
 authors = [
     "AWS Rust SDK Team <[email protected]>",
 ]

rust-runtime/aws-smithy-dns/Cargo.toml

@@ -20,7 +20,7 @@ use hickory_resolver::{
 ///
 /// This resolver requires a [tokio] runtime to function and isn't available for WASM targets.
 #[non_exhaustive]
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct HickoryDnsResolver {
     resolver: Resolver<TokioConnectionProvider>,
 }

rust-runtime/aws-smithy-dns/src/hickory.rs

@@ -1,6 +1,6 @@
 [package]
 name = "aws-smithy-runtime"
-version = "1.9.1"
+version = "1.9.2"
 authors = ["AWS Rust SDK Team <[email protected]>", "Zelda Hessler <[email protected]>"]
 description = "The new smithy runtime crate"
 edition = "2021"

rust-runtime/aws-smithy-runtime/Cargo.toml

@@ -15,7 +15,7 @@ mod tokio {
     ///
     /// This implementation isn't available for WASM targets.
     #[non_exhaustive]
-    #[derive(Debug, Default)]
+    #[derive(Debug, Default, Clone)]
     pub struct TokioDnsResolver;
 
     impl TokioDnsResolver {