Update CI tests to 1.11 due to PG

Author: josevalim

.github/workflows/ci.yml

@@ -24,7 +24,7 @@ jobs:
       fail-fast: false
       matrix:
         elixirbase:
-          - "1.10.4-erlang-21.3.8.24-alpine-3.13.3"
+          - "1.11.4-erlang-21.3.8.24-alpine-3.13.3"
         postgres:
           - "11.11"
           - "9.6"
@@ -43,7 +43,7 @@ jobs:
       fail-fast: false
       matrix:
         elixirbase:
-          - "1.10.4-erlang-21.3.8.24-alpine-3.13.3"
+          - "1.11.4-erlang-21.3.8.24-alpine-3.13.3"
         mysql:
           - "5.7"
     steps:
@@ -60,7 +60,7 @@ jobs:
       fail-fast: false
       matrix:
         elixirbase:
-          - "1.10.4-erlang-21.3.8.24-alpine-3.13.3"
+          - "1.11.4-erlang-21.3.8.24-alpine-3.13.3"
         mssql:
           - "2017"
           - "2019"