updating variable name

Author: Aaron Hill

samples/language/text_analytics_samples.py

@@ -149,5 +149,5 @@ def entity_recognition():
 
     sys.path.append(os.path.abspath(os.path.join(__file__, "..", "..")))
     from tools import execute_samples
-
-    execute_samples(globals(), key)
+    key_env_name = "TEXTANALYTICS_SUBSCRIPTION_KEY"
+    execute_samples(globals(), key_env_name)