Fix formatting of CliUnstable parsing (#15434)

Because the last string in this match statement was over 100 characters,
it prevented rustfmt from formatting the entire thing. By wrapping it,
that allows rustfmt to do its job.

Author: weihanglo

src/cargo/core/features.rs

@@ -1279,10 +1279,8 @@ impl CliUnstable {
             "feature-unification" => self.feature_unification = parse_empty(k, v)?,
             "gc" => self.gc = parse_empty(k, v)?,
             "git" => {
-                self.git = v.map_or_else(
-                    || Ok(Some(GitFeatures::all())),
-                    |v| parse_git(v.split(',')),
-                )?
+                self.git =
+                    v.map_or_else(|| Ok(Some(GitFeatures::all())), |v| parse_git(v.split(',')))?
             }
             "gitoxide" => {
                 self.gitoxide = v.map_or_else(
@@ -1297,7 +1295,7 @@ impl CliUnstable {
             // can also be set in .cargo/config or with and ENV
             "mtime-on-use" => self.mtime_on_use = parse_empty(k, v)?,
             "no-index-update" => self.no_index_update = parse_empty(k, v)?,
-            "package-workspace" => self.package_workspace= parse_empty(k, v)?,
+            "package-workspace" => self.package_workspace = parse_empty(k, v)?,
             "panic-abort-tests" => self.panic_abort_tests = parse_empty(k, v)?,
             "public-dependency" => self.public_dependency = parse_empty(k, v)?,
             "profile-rustflags" => self.profile_rustflags = parse_empty(k, v)?,
@@ -1315,10 +1313,13 @@ impl CliUnstable {
             "target-applies-to-host" => self.target_applies_to_host = parse_empty(k, v)?,
             "unstable-options" => self.unstable_options = parse_empty(k, v)?,
             "warnings" => self.warnings = parse_empty(k, v)?,
-            _ => bail!("\
+            _ => bail!(
+                "\
             unknown `-Z` flag specified: {k}\n\n\
-            For available unstable features, see https://doc.rust-lang.org/nightly/cargo/reference/unstable.html\n\
-            If you intended to use an unstable rustc feature, try setting `RUSTFLAGS=\"-Z{k}\"`"),
+            For available unstable features, see \
+            https://doc.rust-lang.org/nightly/cargo/reference/unstable.html\n\
+            If you intended to use an unstable rustc feature, try setting `RUSTFLAGS=\"-Z{k}\"`"
+            ),
         }
 
         Ok(())