add shaped_grid_positioning test

e2etests/regression_test.go

@@ -1050,6 +1050,7 @@ cf many required: {
 		loadFromFile(t, "grid_rows_gap_bug"),
 		loadFromFile(t, "grid_image_label_position"),
 		loadFromFile(t, "glob_dimensions"),
+		loadFromFile(t, "shaped_grid_positioning"),
 	}
 
 	runa(t, tcs)

e2etests/testdata/files/shaped_grid_positioning.d2

@@ -0,0 +1,39 @@
+vars: {
+  grid-container: {
+    label: aaaaaaaaaaaaaaa aaaaaaaaaaaaaaa
+    grid-rows: 2
+    grid-columns: 2
+    a
+    b
+    c
+    d
+  }
+}
+circle: {
+  shape: circle
+  ...${grid-container}
+}
+
+oval: {
+  shape: oval
+  ...${grid-container}
+}
+
+diamond: {
+  shape: diamond
+  ...${grid-container}
+}
+
+square: {
+  shape: square
+  ...${grid-container}
+}
+
+rect: {
+  ...${grid-container}
+}
+
+cloud: {
+  shape: cloud
+  ...${grid-container}
+}