add day15 solution by spamegg (#476)

* add day15 solution by spamegg

* Update docs/2023/puzzles/day15.md

---------

Co-authored-by: Jamie Thompson <[email protected]>

Author: spamegg1

docs/2023/puzzles/day15.md

@@ -201,9 +201,9 @@ end part2
 
 ## Solutions from the community
 
+- [Solution](https://github.com/spamegg1/advent-of-code-2023-scala/blob/solutions/15.worksheet.sc#L208) by [Spamegg](https://github.com/spamegg1)
 - [Solution](https://github.com/YannMoisan/advent-of-code/blob/master/2023/src/main/scala/Day15.scala) by [YannMoisan](https://github.com/YannMoisan)
+- [Solution](https://github.com/xRuiAlves/advent-of-code-2023/blob/main/Day15.scala) by [Rui Alves](https://github.com/xRuiAlves/)
 
 Share your solution to the Scala community by editing this page.
 You can even write the whole article! [See here for the expected format](https://github.com/scalacenter/scala-advent-of-code/discussions/424)
-
-- [Solution](https://github.com/xRuiAlves/advent-of-code-2023/blob/main/Day15.scala) by [Rui Alves](https://github.com/xRuiAlves/)