Fixes Texture2dParameter node filter option

This bug was appending 2 colons in the generated code.  Fixed it.

scene/resources/visual_shader_nodes.cpp

@@ -6346,6 +6346,7 @@ String get_sampler_hint(VisualShaderNodeTextureParameter::TextureType p_texture_
 		if (!repeat_code.is_empty()) {
 			if (!has_colon) {
 				code += " : ";
+				has_colon = true;
 			} else {
 				code += ", ";
 			}
@@ -6353,6 +6354,7 @@ String get_sampler_hint(VisualShaderNodeTextureParameter::TextureType p_texture_
 		}
 	}
 
+	// source
 	{
 		String source_code;