pin sls version (#11)

Author: BenTheKlein

.circleci/config.yml

@@ -19,7 +19,7 @@ jobs:
       - run:
           name: Install Serverless CLI and dependencies
           command: |
-            sudo npm i -g serverless        
+            sudo npm i -g serverless@2.71.0
             pip install -r requirements.txt -t .    
             
   deploy-staging:
@@ -32,7 +32,7 @@ jobs:
       - run:
           name: Install Serverless CLI and dependencies
           command: |
-            sudo npm i -g serverless            
+            sudo npm i -g serverless@2.71.0
             pip install -r requirements.txt -t .
       - run:
           name: Deploy application to staging
@@ -58,7 +58,7 @@ jobs:
       - run:
           name: Install Serverless CLI and dependencies
           command: |
-            sudo npm i -g serverless            
+            sudo npm i -g serverless@2.71.0
             pip install -r requirements.txt -t .
 
       - run: