Add tool to simulate a release dry run (#3327)

## Motivation and Context
As we discovered in #3318, it's possible to cause unexpected breakage by
releasing runtime crates.
 
This tool automates setting up `aws-sdk-rust` (and manually, you can
copy the patches into `~/.cargo/config.toml` for your entire system), to
simulate the release of new runtime crates.

<img width="1518" alt="Screenshot 2023-12-15 at 12 58 41 PM"
src="https://github.com/smithy-lang/smithy-rs/assets/492903/59d6cb5c-d39c-4e42-98e2-6858d0884449">


### Testing
With this tool (and a small hack—I had to simulate releasing 1.1.100 so
that the versions became the latest), I correctly caught the breaking
changes from the previous release.


----

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choice._

Author: rcoh

tools/ci-build/runtime-release-dryrun/Cargo.lock

@@ -0,0 +1,11 @@
+[package]
+name = "runtime-release-dryrun"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+clap = { version = "4", features = ["derive"] }
+anyhow = "1.0.75"
+indicatif = "0.17.7"