Remove focus outline from navigation items

Removing outline from app navigation to allow for custom
Bootstrap box-shadow focus styles. Explicitly set outline
property to none to override default user agent styles.
Needed to apply to <li> and <a> (nav-item and nav-link).

Signed-off-by: Yoshie Muranaka <yoshiemuranaka@gmail.com>
Change-Id: Iaf70215c68b91fd03f595487a30e93e024c12a1d
diff --git a/src/components/AppNavigation/AppNavigation.vue b/src/components/AppNavigation/AppNavigation.vue
index 5196099..2081609 100644
--- a/src/components/AppNavigation/AppNavigation.vue
+++ b/src/components/AppNavigation/AppNavigation.vue
@@ -165,8 +165,13 @@
   padding-left: 0;
   margin-left: 0;
 
+  .nav-item {
+    outline: none;
+  }
+
   .nav-link {
     padding-left: $spacer * 4;
+    outline: none;
 
     &:not(.nav-link--current) {
       font-weight: normal;