Add tox env verifying plain install (without dev requirements).

Author: chenkins

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-env_list = py{310,311,312},notebooks,py{310,311,312}-ml
+env_list = py{310,311,312},notebooks,py{310,311,312}-ml,py{310,311,312}-verify-install
 
 [gh-actions]
 python =
@@ -123,3 +123,10 @@ deps =
     -r requirements-dev.txt
 commands =
     python -m build
+
+[testenv:py{310,311,312}-verify-install]
+# install flatland-rl without additional dependencies
+skip_install = false
+commands =
+    python --version
+    python -c 'from flatland.evaluators.service import FlatlandRemoteEvaluationService'