Roll dart_style into the SDK.

This doesn't roll the latest dart_style main branch in because that has some style changes and there are other style changes still in flight. I want to roll all of those in all in one batch later.

Instead, this brings in a single commit whose parent is the current dart_style commit in the SDK. That commit contains only a fix for a crash bug when an analysis_options.yaml file contains an include pointing to a non-existent file. See:

https://github.com/dart-lang/dart_style/pull/1855

This gets the main branch in sync with the stable branch which has a cherry-pick with that same fix.

Change-Id: I97e3adec1c93175d372bb972989fe6a2860cf31f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/510222
Auto-Submit: Bob Nystrom <rnystrom@google.com>
Commit-Queue: Bob Nystrom <rnystrom@google.com>
Reviewed-by: Alexander Thomas <athom@google.com>

CHANGELOG.md

@@ -129,8 +129,6 @@ To learn more about the feature, check out the
 
 [analyzer plugins]: https://dart.dev/tools/analyzer-plugins
 
-#### Dart format
-
 These changes are not language versioned and affect formatting all code:
 
 - Fix a bug where some collections or arguments might split unnecessarily.

DEPS

@@ -129,7 +129,7 @@ vars = {
   #   and land the review.
   #
   # For more details, see https://github.com/dart-lang/sdk/issues/30164.
-  "dart_style_rev": "f1d10e1e052116aeb3851f90ace55e5447b3bc21", # rolled manually
+  "dart_style_rev": "2ed8c591717128b3c9c19a95698c1a758ae1c04b", # rolled manually
 
   ### /third_party/pkg dependencies
   # 'tools/rev_sdk_deps.dart' will rev pkg dependencies to their latest; put an