add bandwagoner test

Using custom types and records

bandwagoner/gleam.toml

@@ -0,0 +1,14 @@
+name = "bandwagoner"
+version = "0.1.0"
+
+[dependencies]
+gleam_otp = "~> 0.7 or ~> 1.0"
+gleam_stdlib = ">= 0.54.0 or ~> 1.0"
+simplifile = "~> 1.0"
+gleam_erlang = ">= 0.25.0 and < 1.0.0"
+gleam_yielder = ">= 1.1.0 and < 2.0.0"
+gleam_regexp = ">= 1.1.0 and < 2.0.0"
+gleam_deque = ">= 1.0.0 and < 2.0.0"
+
+[dev-dependencies]
+exercism_test_runner = "~> 1.9"