perf: check test file suffix before the go env lookup (#593)

Author: fredrikaverpil

lua/neotest-golang/init.lua

@@ -95,13 +95,13 @@ end
 --- @param file_path string
 --- @return boolean
 function M.Adapter.is_test_file(file_path)
-  if not go_available() then
+  if not vim.endswith(file_path, "_test.go") then
     return false
   end
-  if lib.goenv.should_skip(file_path, vim.uv.cwd()) then
+  if not go_available() then
     return false
   end
-  return vim.endswith(file_path, "_test.go")
+  return not lib.goenv.should_skip(file_path, vim.uv.cwd())
 end
 
 --- Given a file path, parse all the tests within it.