feat: split out test files and execute them manually

This breaks the old grouping mechanism, but honestly that was a weird way of doing it.

tests/unit/trace.bats

@@ -0,0 +1,52 @@
+#!/usr/bin/env bats
+
+load test_helper
+
+setup() {
+  global_setup
+  rm -f "$DOKKU_ROOT/.dokkurc/DOKKU_TRACE"
+}
+
+teardown() {
+  rm -f "$DOKKU_ROOT/.dokkurc/DOKKU_TRACE"
+  global_teardown
+}
+
+@test "(trace) trace:help" {
+  run /bin/bash -c "dokku trace"
+  echo "output: $output"
+  echo "status: $status"
+  assert_output_contains "Manage trace mode"
+  help_output="$output"
+
+  run /bin/bash -c "dokku trace:help"
+  echo "output: $output"
+  echo "status: $status"
+  assert_output_contains "Manage trace mode"
+  assert_output "$help_output"
+}
+
+@test "(trace) trace:on" {
+  run /bin/bash -c "dokku trace:on"
+  echo "output: $output"
+  echo "status: $status"
+  assert_success
+
+  run /bin/bash -c "test -f $DOKKU_ROOT/.dokkurc/DOKKU_TRACE"
+  echo "output: $output"
+  echo "status: $status"
+  assert_success
+}
+
+@test "(trace) trace:off, trace off" {
+  touch "$DOKKU_ROOT/.dokkurc/DOKKU_TRACE"
+  run /bin/bash -c "dokku trace:off"
+  echo "output: $output"
+  echo "status: $status"
+  assert_success
+
+  run /bin/bash -c "test -f $DOKKU_ROOT/.dokkurc/DOKKU_TRACE"
+  echo "output: $output"
+  echo "status: $status"
+  assert_failure
+}