Fix GUI debug console traffic graph legend colors

The stylesheets override the custom palette colors for line widgets.
This sets the colors for the traffic graph legend with style rules.

Author: cyrossignol

src/qt/res/stylesheets/dark_stylesheet.qss

@@ -803,3 +803,13 @@ QStatusBar QToolTip {
 #consolidateSendReadyLabel{
     color: rgb(55, 250, 55);
 }
+
+/* Debug Console */
+
+RPCConsole #greenLine {
+    border-top-color: rgb(0, 255, 0);
+}
+
+RPCConsole #redLine {
+    border-top-color: rgb(255, 0, 0);
+}

src/qt/res/stylesheets/light_stylesheet.qss

@@ -800,3 +800,13 @@ QStatusBar .QFrame QLabel {
 #consolidateSendReadyLabel{
     color: rgb(0, 128, 0);
 }
+
+/* Debug Console */
+
+RPCConsole #greenLine {
+    border-top-color: rgb(0, 255, 0);
+}
+
+RPCConsole #redLine {
+    border-top-color: rgb(255, 0, 0);
+}