Bring test suite up to date

test/data/home-module-graph/errors/A.hs

@@ -0,0 +1,4 @@
+module A where
+import A1
+import A2
+import A3

test/data/home-module-graph/errors/A1.hs

@@ -0,0 +1,4 @@
+module A1 where
+psogduapzsü9
+import B
+lxäö,vLMCks

test/data/home-module-graph/errors/A2.hs

@@ -0,0 +1 @@
+module A2 where

test/data/home-module-graph/errors/A3.hs

@@ -0,0 +1,2 @@
+module A3 where
+import B

test/data/home-module-graph/errors/B.hs

@@ -0,0 +1 @@
+module B where