Move betterproto/tests → tests

tests/inputs/import_child_package_from_root/child.proto

@@ -0,0 +1,7 @@
+syntax = "proto3";
+
+package childpackage;
+
+message Message {
+
+}

tests/inputs/import_child_package_from_root/import_child_package_from_root.proto

@@ -0,0 +1,9 @@
+syntax = "proto3";
+
+import "child.proto";
+
+// Tests generated imports when a message in root refers to a message in a child package.
+
+message Test {
+  childpackage.Message child = 1;
+}