Use 4chan's color for greentext, but only for .greentext

Self-explanatory. I think this is more appropriate, and I didn't make a special variable for it because I can't imagine this exact color getting used anywhere but specifically for greentext.

src/components/status_content/status_content.vue

@@ -225,8 +225,8 @@ $status-margin: 0.75em;
 }
 
 .greentext {
-  color: $fallback--cGreen;
-  color: var(--cGreen, $fallback--cGreen);
+  color: $fallback--greentext;
+  color: var(--greentext, $fallback--greentext);
 }
 
 .timeline :not(.panel-disabled) > {