linter avoid_field_initializers_in_const_classes cherry-pick

Cherry-picks a fix to `avoid_field_initializers_in_const_classes` (dart-lang/linter#3974).

git log:

commit 8f7b75f8a3501ca2c4d5bbc1f003d90d66447544 (HEAD -> release, origin/release)
Author: Phil Quitslund <pq@users.noreply.github.com>
Date:   Mon Jan 9 09:39:48 2023 -0800

    remove unsafe null-check (#3975)

commit 79b8433
Author: Phil Quitslund <pq@users.noreply.github.com>
Date:   Thu Dec 15 09:50:23 2022 -0800

    1.32.0 (#3916)


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Change-Id: I57afab3aadf23da96a2e9f596edfde5db71297ec
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/278685
Commit-Queue: Phil Quitslund <pquitslund@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>

DEPS

@@ -139,7 +139,7 @@ vars = {
   "intl_rev": "c61fdd19c5a1a72b60d58152e2860f08725d188b",
   "jinja2_rev": "2222b31554f03e62600cd7e383376a7c187967a1",
   "json_rpc_2_rev": "bd9f8d90ec9ce9d0da5c11f3e71b87af3aaca3b4",
-  "linter_rev": "79b843349deaea4a2455cfa37cc47cbc0e472190", # 1.32.0
+  "linter_rev": "8f7b75f8a3501ca2c4d5bbc1f003d90d66447544", # 1.32.0 (avoid_field_initializers_in_const_classes cherry-pick)
   "lints_rev": "dfded5e265015f21ce154577fe8488dc244e33c2",
   "logging_rev": "b525d5c39c8ae6f0826c63a371d286080e2ec93e",
   "markdown_rev": "ee3f4e976efcfed87c6ec78364bc2dd3c6e717b9", # https://github.com/dart-lang/markdown/pull/494