Fix `append_text_comment` rule to support multiline comments

[jeparlefrancais]

• [x] add entry to the changelog

[github-actions[bot]]

Coverage after merging fix-append-multiline-comment into main will be

87.07%

Coverage Report for Changed Files

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
src/rules
append_text_comment.rs	51.58%	100%	62.86%	50.68%	119–126, 142–155, 161–172, 178–187, 193–202, 208–224, 230–241, 247–254, 260–268, 283–301, 322–329, 332–334, 336–338, 348–349, 351–352, 361–363, 367–369, 37, 371–372, 38, 380–381, 386–389, 39, 390–394, 40, 407–408, 41, 414–419, 42, 420–421, 43, 451–456, 463, 476, 484–499, 506–508, 54, 56–59, 73–74