Update panel.adoc

Removed unneeded new line breaks.

src/docs/asciidoc/jme3/contributions/tonegodgui/panel.adoc

@@ -15,7 +15,7 @@ The Panel class extends Element and, like the Label class, it’s only purpose i
 .  The 3 standard constructors as shown in the <<jme3/contributions/tonegodgui/quickstart#,Quick Start Guide>>
 .  Default style information
 
-*Constructor 1:*+
+*Constructor 1:*
 
 [source,java]
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@@ -30,7 +30,7 @@ Panel panel = new Panel(screen, “panel”, new Vector2f(15, 15));
 
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-*Constructor 2:*+
+*Constructor 2:*
 
 [source,java]
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@@ -44,7 +44,7 @@ Panel panel = new Panel(screen, “panel”, new Vector2f(15, 15),
 
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-*Constructor 3:*+
+*Constructor 3:*
 
 [source,java]
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