Use the 'dot' utf-8 encoded value instead of the char directly

Compilation was broken on latest Debian Sid (gcc-13) complaining
about unmappable character (0xE2) for encoding US-ASCII.

The commit change the utf-8 dot char by its encoded representation
\u2022.

Signed-off-by: Jose Luis Rivero <jrivero@osrfoundation.org>

lcm-java/lcm/logging/LogPlayer.java

@@ -1120,7 +1120,7 @@ public void windowClosing(WindowEvent e) {
             }
 
             {
-                String spacer = "  •  ";
+                String spacer = "  \u2022  ";
                 String filename = p.logName.getText();
 
                 String title = "LogPlayer";

lcm-java/lcm/spy/Spy.java

@@ -38,7 +38,7 @@ public Spy(String lcmurl, WindowTitleOptions titleOptions) throws IOException
         }
         String title = "LCM Spy";
         {
-            String spacer = "  •  ";
+            String spacer = "  \u2022  ";
             if (null != titleOptions.label) {
                 title += spacer + titleOptions.label;
             }