bump rust-toolchain to 1.72.1 (#11079)

# Description

This PR follows our process of staying 2 releases behind rust. 1.74.0
was released today so we update to 1.72.1.

Reference https://releases.rs/

# User-Facing Changes
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src/tests/test_config_path.rs

@@ -10,7 +10,7 @@ fn adjust_canonicalization<P: AsRef<Path>>(p: P) -> String {
 
 #[cfg(target_os = "windows")]
 fn adjust_canonicalization<P: AsRef<Path>>(p: P) -> String {
-    const VERBATIM_PREFIX: &str = r#"\\?\"#;
+    const VERBATIM_PREFIX: &str = r"\\?\";
     let p = p.as_ref().display().to_string();
     if let Some(stripped) = p.strip_prefix(VERBATIM_PREFIX) {
         stripped.to_string()