Update Agents (#2159)

### Description

Update rust toolchain and packages.

### Drive-by changes

No

### Related issues

### Backward compatibility

_Are these changes backward compatible?_

Yes

_Are there any infrastructure implications, e.g. changes that would
prohibit deploying older commits using this infra tooling?_

None


### Testing

_What kind of testing have these changes undergone?_

Unit Tests

rust-toolchain

@@ -1,3 +1,3 @@
 [toolchain]
-channel = "1.68"
+channel = "1.69"
 profile = "default"

rust/Dockerfile

@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:experimental
 
-FROM rust:1.68 as builder
+FROM rust:1.69 as builder
 WORKDIR /usr/src
 
 # 1a: Prepare for static linking

rust/README.md

@@ -5,13 +5,13 @@
 - install `rustup`
   - [link here](https://rustup.rs/)
 
-Note: You should be running >= version `1.68.0` of the rustc compiler, you can see that version with this command and should see similar output:
+Note: You should be running >= version `1.69.0` of the rustc compiler, you can see that version with this command and should see similar output:
 
 ```
 $ rustup --version
-rustup 1.25.1 (bb60b1e89 2022-07-12)
+rustup 1.26.0 (5af9b9484 2023-04-05)
 info: This is the version for the rustup toolchain manager, not the rustc compiler.
-info: The currently active `rustc` version is `rustc 1.68.0 (2c8cc3432 2023-03-06)`
+info: The currently active `rustc` version is `rustc 1.69.0 (84c898d65 2023-04-16)`
 ```
 
 ### Useful cargo commands

rust/utils/run-locally/Cargo.toml

@@ -11,5 +11,5 @@ version.workspace = true
 ctrlc = "3.2"
 tempfile = "3.3"
 maplit = "1.0"
-nix = { version = "0.25", default-features = false, features = ["signal"] }
+nix = { version = "0.26", default-features = false, features = ["signal"] }
 ureq = { version = "2.4", default-features = false }