Fix Sass build error

Replaced $success-light Sass variable with theme-color-light function.
We removed the variable and forgot to update this partial.

Signed-off-by: Yoshie Muranaka <yoshiemuranaka@gmail.com>
Change-Id: If4422241cae10efdb0e17b31327465ee4d0a6dae
diff --git a/src/assets/styles/bmc/custom/_card.scss b/src/assets/styles/bmc/custom/_card.scss
index 1272189..5f2a596 100644
--- a/src/assets/styles/bmc/custom/_card.scss
+++ b/src/assets/styles/bmc/custom/_card.scss
@@ -1,5 +1,5 @@
 .card {
   .bg-success {
-    background-color: $success-light !important;
+    background-color: theme-color-light('success')!important;
   }
 }
\ No newline at end of file