Renaming a member does not rename references to it in a closure

[ahoppen]

The following new test case fails to rename x to yyy inside runClosure

try await assertSingleFileRename(
  """
  func runClosure(body: () -> Void) {}

  struct Foo {
    var 1️⃣x: Int

    func foo() {
      runClosure {
        x = 2
      }
    }
  }
  """,
  newName: "yyy",
  expectedPrepareRenamePlaceholder: "x",
  expected: """
  func runClosure(body: () -> Void) {}

  struct Foo {
    var yyy: Int

    func foo() {
      runClosure {
        yyy = 2
      }
    }
  }
  """
)