Delete unused CCheckbox text setting remains following b1422137e5, refs 0f807c643a.

Differential Revision: https://code.wildfiregames.com/D2314
Tested on: clang 8.0.1., Jenkins

This was SVN commit r22952.

binaries/data/mods/mod/gui/common/modern/styles.xml

@@ -139,7 +139,6 @@
 		sprite2="ModernTickOn"
 		sprite_disabled="ModernTickDisabledOff"
 		sprite2_disabled="ModernTickDisabledOn"
-		square_side="22"
 		sound_pressed="audio/interface/ui/ui_button_click.ogg"
 	/>
 	<style name="ModernSlider"

binaries/data/mods/mod/gui/modmod/modmod.xml

@@ -29,7 +29,6 @@
 				checked="false"
 				style="ModernTickBox"
 				size="186 0 206 100%"
-				font="serif-bold-13"
 			>
 				<action on="Press">applyFilters();</action>
 			</object>

binaries/data/mods/public/gui/lobby/lobby_panels.xml

@@ -243,12 +243,7 @@
 			<object type="text" size="22 0 52%-10 100%" text_align="left" textcolor="white">
 				<translatableAttribute id="caption">Show only open games</translatableAttribute>
 			</object>
-			<object name="filterOpenGames"
-				type="checkbox"
-				checked="false"
-				style="ModernTickBox"
-				size="0 0 20 20"
-				font="sans-bold-13">
+			<object name="filterOpenGames" type="checkbox" checked="false" style="ModernTickBox" size="0 0 20 20">
 				<action on="Press">
 					applyFilters();
 				</action>