Add fs_mgr_unit_test to CTS

Test: atest --rebuild-module-info CtsFsMgrTestCases
Bug: 135984674
Change-Id: I72c60ec8acdcb3539da091abb4f84e0bc3c6743b
diff --git a/TEST_MAPPING b/TEST_MAPPING
index cc1978d..375207b 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -10,7 +10,7 @@
       "name": "debuggerd_test"
     },
     {
-      "name": "fs_mgr_unit_test"
+      "name": "CtsFsMgrTestCases"
     },
     {
       "name": "fs_mgr_vendor_overlay_test"