Fix minimum compatible version of Julia and run CI on 1.5 and 1

.github/workflows/ci.yml

@@ -14,6 +14,8 @@ jobs:
       fail-fast: false
       matrix:
         version:
+          - '1.5' # Oldest supported version of SBML.jl
+          - '1' # This is always the latest stable release in the 1.X series
           - 'nightly'
         os:
           - ubuntu-latest

Project.toml

@@ -13,7 +13,7 @@ Symbolics = "0c5d862f-8b57-4792-8d23-62f2024744c7"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [compat]
-julia = "1"
+julia = "1.5"
 Symbolics = "1.1"
 
 [extras]