give the linux test job 30m for the full divergence pipeline

with the divergence harness now passing (rather than being killed at 60s),
the linux job runs its whole pipeline — tests + doctests + dogfood + docs —
which needs more than the upstream 20m budget on the slower fork runner

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: KotlinIsland

.github/workflows/ci.yaml

@@ -306,7 +306,10 @@ jobs:
     runs-on: ${{ github.repository == 'astral-sh/ruff' && 'depot-ubuntu-22.04-16' || 'ubuntu-latest' }}
     needs: determine_changes
     if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') && (needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main') }}
-    timeout-minutes: 20
+    # the basedpython divergence harness transpiles + runs every mdtest block
+    # through a subprocess and provisions python via uv, so the full pipeline
+    # (tests + doctests + dogfood + docs) runs longer than the upstream 20m
+    timeout-minutes: 30
     env:
       # Line-tables-only debug info: faster builds, backtraces still work.
       CARGO_PROFILE_DEV_DEBUG: line-tables-only