docs: add neotest-kotlin (#436)

Co-authored-by: Cody Mikol <[email protected]>

README.md

@@ -118,6 +118,7 @@ See the adapter's documentation for their specific setup instructions.
 | haskell           |     [neotest-haskell](https://github.com/mrcjkb/neotest-haskell)     |
 | deno              |      [neotest-deno](https://github.com/MarkEmmons/neotest-deno)      |
 | java              |        [neotest-java](https://github.com/rcasia/neotest-java)        |
+| kotlin              |        [neotest-kotlin](https://github.com/codymikol/neotest-kotlin.nvim)        |
 | foundry           |    [neotest-foundry](https://github.com/llllvvuu/neotest-foundry)    |
 | zig               |      [neotest-zig](https://github.com/lawrence-laz/neotest-zig)      |
 | c++ (google test) |       [neotest-gtest](https://github.com/alfaix/neotest-gtest)       |