Log per-test durations during integration tests

To spot slow or anomalous tests across CI runs, record each test's run
duration when LAZYGIT_TEST_TIMING is set (to a file path);
run_integration_tests.sh prints them at the end, sorted by slowest
first. CI sets it for all integration jobs.

The harness appends to a file rather than writing to stdout/stderr
because `go test` captures those and only surfaces them with -v, which
would drown the signal in every test's verbose logs.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.github/workflows/ci.yml

@@ -109,6 +109,9 @@ jobs:
           # by default on the Linux runner, but we set it explicitly to be safe.
           LAZYGIT_RACE_DETECTOR: ${{ matrix.race && '1' || '' }}
           CGO_ENABLED: ${{ matrix.race && '1' || '' }}
+          # Append each test's duration to this file; run_integration_tests.sh
+          # prints the slowest at the end, to spot slow/anomalous tests.
+          LAZYGIT_TEST_TIMING: /tmp/test_timings.txt
         run: |
           mkdir -p /tmp/code_coverage
           ./scripts/run_integration_tests.sh