[instancer] enable the missing test

test/subset/data/Makefile.am

@@ -61,6 +61,7 @@ EXTRA_DIST += \
 	expected/instantiate_glyf \
 	expected/pin_all_at_default \
 	expected/instance_no_double_free \
+	expected/mvar_full_instance \
 	fonts \
 	profiles \
 	$(NULL)

test/subset/data/Makefile.sources

@@ -52,6 +52,7 @@ TESTS = \
 	tests/instantiate_glyf.tests \
 	tests/pin_all_at_default.tests \
 	tests/instance_no_double_free.tests \
+	tests/mvar_full_instance.tests \
 	$(NULL)
 
 # TODO: re-enable once colrv1 subsetting is stabilized.

test/subset/meson.build

@@ -54,6 +54,7 @@ tests = [
   'full_instance',
   'instance_feature_variations',
   'instance_no_double_free',
+  'mvar_full_instance',
 ]
 
 repack_tests = [