Add python bindings for IREE internal dialects. (#14770)

I've been running into these recently when wanting to create helper
scripts. Also some of these will be helpful for Turbine.
diff --git a/compiler/bindings/python/test/ir/CMakeLists.txt b/compiler/bindings/python/test/ir/CMakeLists.txt
index c49e26d..fcf7b13 100644
--- a/compiler/bindings/python/test/ir/CMakeLists.txt
+++ b/compiler/bindings/python/test/ir/CMakeLists.txt
@@ -11,3 +11,9 @@
     "registration_test.py"
 )
 
+iree_py_test(
+  NAME
+    dialects_test
+  SRCS
+    "dialects_test.py"
+)
diff --git a/compiler/bindings/python/test/ir/dialects_test.py b/compiler/bindings/python/test/ir/dialects_test.py
new file mode 100644
index 0000000..63a9603
--- /dev/null
+++ b/compiler/bindings/python/test/ir/dialects_test.py
@@ -0,0 +1,16 @@
+# Copyright 2023 The IREE Authors
+#
+# Licensed under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+from iree.compiler import ir
+
+# Make sure that our dialects import.
+from iree.compiler.dialects import (
+    flow,
+    hal,
+    stream,
+    vm,
+    util,
+)