Downgrade to cimg/go:1.19.1, which is using Ubuntu 20.04

This makes the binaries compatible with Ubuntu 20.04 again.

Author: g3force

.circleci/config.yml

@@ -27,7 +27,7 @@ jobs:
   test_go:
     resource_class: medium
     docker:
-      - image: cimg/go:1.20.3
+      - image: cimg/go:1.19.1
     steps:
       - checkout
       - attach_workspace:
@@ -42,7 +42,7 @@ jobs:
   build_go:
     resource_class: large
     docker:
-      - image: cimg/go:1.20.3
+      - image: cimg/go:1.19.1
     steps:
       - checkout
       - attach_workspace:
@@ -71,7 +71,7 @@ jobs:
   publish_gh:
     resource_class: small
     docker:
-      - image: cimg/go:1.20.3
+      - image: cimg/go:1.19.1
     steps:
       - attach_workspace:
           at: .