Revert "don't test on julia 1.0 since we require 1.3"

This reverts commit 2f81405.

Author: stevengj

.github/workflows/ci.yml

@@ -15,6 +15,7 @@ jobs:
       matrix:
         version:
           - "1.3"
+          - "1"
           - "nightly"
         os:
           - ubuntu-latest