Possibly unexpected slot machine display

[YuevUwU]

問題說明 Describe the feature
當前老虎機顯示採用10個圖標的循環圖，根據代碼可能有潛在未預期的抽選(只影響顯示)

• randomSlot() 僅會生成 1-9 的可能 (all different or one pair)
• all same 事件只會產生 0-8 的可能( 根據 Math.random()∊[0,1) )
• all same 事件可能與lightning有相同結果，造成明明 ⚡ ⚡ ⚡ 卻不值 50 電電點

_{(此issue僅從 templates/slot.html 分析，可能有其他機制避免或此為預期，如有錯誤，在此先行道歉)}

The current slot machine display uses an image of 10 icons cyclically.
Depending on the code, there may be potentially unexpected draws (only affects the display).

• randomSlot() will only generate possibilities 1-9 during all different and one pair
• Will only produce 0-8 possibilities during all same (according to Math.random()∊[0,1) )
• May have the same result as lightning during all same, even if get ⚡ ⚡ ⚡ but it doesn't worth 50 :zap~1:

_{(This issue is only analyzed from templates/slot.html. There may be other mechanisms to avoid this or this is expected. If I made any mistake, I apologize first)}

Expected behavior

• 在 slot.png 的圖標都能正常顯示 The icons in slot.png can be displayed normally
• ⚡ ⚡ ⚡ 僅存在於lightning發生時 ⚡ ⚡ ⚡ only exists during lightning

[elvisdragonmao]

又 assign 給我，莫名其妙（

[winstonsung]

噢，按到了。