Update setup.py

Version update along with google-cloud-spanner version requirements update.

Author: cqian23

setup.py

@@ -33,10 +33,10 @@ def package_files(directory):
 
 setup(
     name="spanner-graph-notebook",
-    version="v1.1.8",
+    version="v1.1.9",
     packages=find_packages(),
     install_requires=[
-        "networkx", "numpy", "google-cloud-spanner", "ipython",
+        "networkx", "numpy", "google-cloud-spanner>=3.65.0", "ipython",
         "ipywidgets", "notebook", "requests", "portpicker",
         "pydata-google-auth"
     ],