bump rust toolchain to 1.96.1 (#18968)

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## Description
This PR bumps nushell to the rust toolchain version 1.96.1
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Cargo.toml

@@ -1,7 +1,7 @@
 [workspace.package]
 authors = ["The Nushell Project Developers"]
 edition = "2024"
-rust-version = "1.95.0"
+rust-version = "1.96.1"
 license = "MIT"
 version = "0.115.2"
 

rust-toolchain.toml

@@ -14,4 +14,4 @@ profile = "default"
 # so that we give repo maintainers and package managers a chance to update to a more
 # recent version of rust. However, if there is a "cool new feature" that we want to
 # use in nushell, we may opt to use the bleeding edge stable version of rust.
-channel = "1.95.0"
+channel = "1.96.1"