Test oldest ST version marked in PC

Author: Michael Lyons

.github/workflows/syntax.yml

@@ -35,7 +35,7 @@ jobs:
       matrix:
         include:
           - build: 'latest'
-          # - build: 3211  # libgl1-mesa-glx is not available on ubuntu-latest SublimeText/syntax-action#17
+          - build: 4075  # Earliest supported version noted in Package Control
     steps:
       - uses: actions/checkout@v4
       - uses: SublimeText/syntax-test-action@v2