[ImgBot] Optimize images

*Total -- 36.68kb -> 18.96kb (48.3%)

/solution/0100-0199/0141.Linked List Cycle/images/circularlinkedlist.png -- 11.04kb -> 4.03kb (63.45%)
/solution/0100-0199/0141.Linked List Cycle/images/circularlinkedlist_test2.png -- 4.47kb -> 2.07kb (53.73%)
/solution/0100-0199/0141.Linked List Cycle/images/circularlinkedlist_test3.png -- 1.92kb -> 0.93kb (51.45%)
/solution/0100-0199/0142.Linked List Cycle II/images/linked-list-cycle-ii.png -- 19.25kb -> 11.93kb (38.04%)

Signed-off-by: ImgBotApp <[email protected]>

Author: ImgBotApp