Merge pull request #1649 from scala-steward-org/topic/immutable-refs-cats-2-2-0-migration

Use immutable references for the Cats 2.2.0 Scalafix migration

Author: fthomas

modules/core/src/main/resources/scalafix-migrations.conf

@@ -94,8 +94,8 @@ migrations = [
     groupId: "org.typelevel",
     artifactIds: ["cats-core"],
     newVersion: "2.2.0",
-    rewriteRules: ["github:typelevel/cats/Cats_v2_2_0"],
-    doc: "https://github.com/typelevel/cats/blob/master/scalafix/README.md#migration-to-cats-v220",
+    rewriteRules: ["github:typelevel/cats/Cats_v2_2_0?sha=v2.2.0"],
+    doc: "https://github.com/typelevel/cats/blob/v2.2.0/scalafix/README.md#migration-to-cats-v220",
     scalacOptions: ["-P:semanticdb:synthetics:on"]
   },
   {