Enforce newline after assignment / clause.

This leads to more consistent formatting across entire Aiken programs.
  Before that commit, only long expressions would be formatted on a
  newline, causing non-consistent formatting and additional reading
  barrier when looking at source code.

  Programs also now take more vertical space, which is better for more
  friendly diffing in version control systems (especially git).

examples/acceptance_tests/040/lib/tests.ak

@@ -28,7 +28,8 @@ test expect_ford1() {
         builtin.list_data([]),
       ],
     )
-  expect Ford { owner, wheels, truck_bed_limit, .. }: Car = initial_car
+  expect Ford { owner, wheels, truck_bed_limit, .. }: Car =
+    initial_car
   owner == #"" && wheels == 4 && truck_bed_limit == 10000
 }
 
@@ -41,26 +42,32 @@ test expect_ford2() {
       truck_bed_limit: 15000,
       car_doors: [],
     }
-  expect Ford { owner, wheels, remote_connect, .. } = initial_car
+  expect Ford { owner, wheels, remote_connect, .. } =
+    initial_car
   owner == #"2222222222" && wheels == 6 && remote_connect == #""
 }
 
 test expect_list1() {
-  let initial_car = [5, 6, 7]
-  expect [a, b, c] = initial_car
+  let initial_car =
+    [5, 6, 7]
+  expect [a, b, c] =
+    initial_car
   a == 5 && b == 6 && c == 7
 }
 
 test expect_list2() {
-  let initial_car = [5, 6, 7]
-  expect [a, ..d] = initial_car
+  let initial_car =
+    [5, 6, 7]
+  expect [a, ..d] =
+    initial_car
   a == 5 && d == [6, 7]
 }
 
 test expect_list3() {
   let initial_car =
     builtin.list_data([builtin.i_data(5), builtin.i_data(6), builtin.i_data(7)])
-  expect [a, ..d]: List<Int> = initial_car
+  expect [a, ..d]: List<Int> =
+    initial_car
   a == 5 && d == [6, 7]
 }
 
@@ -69,16 +76,22 @@ type Redeemer {
 }
 
 test single_field_expect() {
-  let redeemer = CreateVoteBatch { id: #"" }
-  expect CreateVoteBatch { id } = redeemer
+  let redeemer =
+    CreateVoteBatch { id: #"" }
+  expect CreateVoteBatch { id } =
+    redeemer
   id == #""
 }
 
 test single_when() {
-  let redeemer = CreateVoteBatch { id: #"" }
-  let x = when redeemer is {
-    CreateVoteBatch { id } -> id == #""
-    _ -> False
-  }
+  let redeemer =
+    CreateVoteBatch { id: #"" }
+  let x =
+    when redeemer is {
+      CreateVoteBatch { id } ->
+        id == #""
+      _ ->
+        False
+    }
   x == True
 }