cargo: Bump rustc to 1.89 (#36818)

Update Rustc to 1.89.

Reviewable by commit.

Leftover work:
- #37330 
- #38777

---------

Signed-off-by: sagudev <16504129+sagudev@users.noreply.github.com>
Co-authored-by: sagudev <16504129+sagudev@users.noreply.github.com>

components/hyper_serde/lib.rs

@@ -431,6 +431,10 @@ impl Serialize for Ser<'_, HeaderMap> {
             {
                 let mut serializer = serializer.serialize_seq(Some(self.0.len()))?;
                 for v in self.0 {
+                    #[allow(
+                        clippy::collapsible_if,
+                        reason = "let chains are not available in 1.85"
+                    )]
                     if self.1 {
                         if let Ok(v) = str::from_utf8(v) {
                             serializer.serialize_element(v)?;