feat: add rockspec

neotest is a common dependency across Neovim plugins. Using luarocks may alleviate the need for users to specify their plugins' dependencies in their plugin manager.
(e.g., vim-plug or packer).

See also:
https://teto.github.io/posts/2021-09-17-neovim-plugin-luarocks.html

neotest-scm-1.rockspec

@@ -0,0 +1,38 @@
+local _MODREV, _SPECREV = 'scm', '-1'
+
+rockspec_format = "3.0"
+package = 'neotest'
+version = _MODREV .. _SPECREV
+
+description = {
+  summary = "A framework for interacting with tests within NeoVim.",
+  detailed = [[
+    See :h neotest for details on neotest is designed and how to interact with it programmatically.
+  ]],
+  homepage = 'https://github.com/nvim-neotest/neotest',
+  license = 'MIT',
+  labels = { 'neovim', 'tree-sitter', 'test' }
+}
+
+dependencies = {
+  'lua == 5.1',
+  'plenary.nvim',
+}
+
+source = {
+  url = 'https://github.com/nvim-neotest/neotest/archive/v' .. _MODREV .. '.zip',
+  dir = 'neotest-' .. _MODREV,
+}
+
+if _MODREV == 'scm' then
+  source = {
+    url = 'git://github.com/nvim-neotest/neotest',
+  }
+end
+
+build = {
+  type = 'builtin',
+  copy_directories = {
+    'doc'
+  }
+}