Fix printing variables that have inherit references in them

Inherit references (@inherit in make, 1-tuples in starlark)
usually appear in list product variables, where they're
evaluated before printing. But sometimes they can be copied
into a regular global variable, in which case they won't
be evaluated before printing. The 1-tuples were failing to
print, so adapt them to their make representation before
printing.

Fixes: 264554449
Test: ./out/rbcrun ./build/make/tests/run.rbc
Change-Id: I5ac6eb996c25ee5e77aa26ed5c4b6b6cc31819d1
diff --git a/tests/run.rbc b/tests/run.rbc
index e8c4caa..1b51719 100644
--- a/tests/run.rbc
+++ b/tests/run.rbc
@@ -28,6 +28,7 @@
 load("//build/make/tests/single_value_inheritance:test.rbc", test_single_value_inheritance = "test")
 load("//build/make/tests/artifact_path_requirements:test.rbc", test_artifact_path_requirements = "test")
 load("//build/make/tests/prefixed_sort_order:test.rbc", test_prefixed_sort_order = "test")
+load("//build/make/tests/inherits_in_regular_variables:test.rbc", test_inherits_in_regular_variables = "test")
 
 def assert_eq(expected, actual):
     if expected != actual:
@@ -176,3 +177,4 @@
 test_single_value_inheritance()
 test_artifact_path_requirements()
 test_prefixed_sort_order()
+test_inherits_in_regular_variables()