fix: Update help headings to match clap

This was missed when upgrading to clap v4

Fixes #11238

Author: epage

src/bin/cargo/commands/add.rs

@@ -83,7 +83,7 @@ Example uses:
         ])
         .arg_quiet()
         .arg_dry_run("Don't actually write the manifest")
-        .next_help_heading("SOURCE")
+        .next_help_heading("Source")
         .args([
             clap::Arg::new("path")
                 .long("path")
@@ -131,7 +131,7 @@ This is the catch all, handling hashes to named references in remote repositorie
                 .value_name("NAME")
                 .help("Package registry for this dependency"),
         ])
-        .next_help_heading("SECTION")
+        .next_help_heading("Section")
         .args([
             flag("dev",
                 "Add as development dependency")

src/bin/cargo/commands/remove.rs

@@ -20,7 +20,7 @@ pub fn cli() -> clap::Command {
         .arg_manifest_path()
         .arg_quiet()
         .arg_dry_run("Don't actually write the manifest")
-        .next_help_heading("SECTION")
+        .next_help_heading("Section")
         .args([
             clap::Arg::new("dev")
                 .long("dev")