Point Doltlite checkout at dolthub/doltlite

The canonical repo is dolthub/doltlite (SQLite 3.54.0 base, actively
developed), not the personal mirror at timsehn/doltlite which trails
behind.

Author: JanJakes

.github/workflows/phpunit-tests-doltlite.yml

@@ -28,7 +28,7 @@ jobs:
       - name: Check out Doltlite
         uses: actions/checkout@v4
         with:
-          repository: timsehn/doltlite
+          repository: dolthub/doltlite
           path: doltlite-src
 
       - name: Build Doltlite shared library