fix: resolve jumanji import crash in non-terminal and non-notebook se…

…tting (#46)

jumanji/environments/__init__.py

@@ -28,6 +28,10 @@ def is_colab() -> bool:
     return "google.colab" in sys.modules
 
 
+def is_notebook() -> bool:
+    return "ipykernel" in sys.modules
+
+
 # In a notebook, force the Matplotlib backend to ngAgg in order for figures to update
 # every time render is called for environments that use Matplotlib
 # for rendering. Without this, only the last render result is shown per figure.
@@ -39,8 +43,10 @@ def is_colab() -> bool:
 
         if is_colab():
             backend = "inline"
-        else:
+        elif is_notebook():
             backend = "notebook"
+        else:
+            backend = ""
         IPython.get_ipython().run_line_magic("matplotlib", backend)
 
 except ImportError as exc: