Backport PR pandas-dev#51886 on branch 2.0.x (CI: Pin moto image to specific version) (pandas-dev#51893)

Backport PR pandas-dev#51886: CI: Pin moto image to specific version

Co-authored-by: Matthew Roeschke <[email protected]>

Author: meeseeksmachine

.github/workflows/ubuntu.yml

@@ -141,7 +141,7 @@ jobs:
           - 5432:5432
 
       moto:
-        image: motoserver/moto
+        image: motoserver/moto:4.1.4
         env:
           AWS_ACCESS_KEY_ID: foobar_key
           AWS_SECRET_ACCESS_KEY: foobar_secret