doc/check-routeros-update: update versions in screenshot

doc/check-routeros-update.d/notification.svg

@@ -171,7 +171,7 @@
 </tspan><tspan
          x="180"
          y="40.85"
-         id="tspan13545">A new RouterOS version 6.48.3 is available for MikroTik.
+         id="tspan13545">A new RouterOS version 7.1.3 is available for MikroTik.
 </tspan><tspan
          x="180"
          y="55.85"
@@ -199,11 +199,11 @@
 </tspan><tspan
          x="180"
          y="145.85"
-         id="tspan13559">    Installed:  6.48.2
+         id="tspan13559">    Installed:  7.1.2
 </tspan><tspan
          x="180"
          y="160.85"
-         id="tspan13561">    Available:  6.48.3
+         id="tspan13561">    Available:  7.1.3
 </tspan><tspan
          x="180"
          y="175.85"
@@ -211,7 +211,7 @@
 </tspan><tspan
          x="180"
          y="190.85"
-         id="tspan13565">    Current:    55</tspan></text>
+         id="tspan13565">    Current:    78</tspan></text>
     <text
        xml:space="preserve"
        id="text6580"