[MM-59811] Fix Incorrect "set custom status" Color (#27777)

* Change: Update color css property to a=0.75 in custom_status__container class

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Co-authored-by: Mattermost Build <build@mattermost.com>

webapp/channels/src/components/status_dropdown/status_dropdown.scss

@@ -193,6 +193,7 @@ button.custom_status__row {
 
     .custom_status__container {
         align-items: center;
+        color: rgba(var(--center-channel-color-rgb), 0.75);
         line-height: 14px;
     }