chore: provide mod:download command and stabilize schedule test (#5000)

# What this PR does

provide mod:download command and stabilize schedule test


## Checklist

- [x] Unit, integration, and e2e (if applicable) tests updated
- [x] Documentation added (or `pr:no public docs` PR label added if not
required)
- [x] Added the relevant release notes label (see labels prefixed w/
`release:`). These labels dictate how your PR will
    show up in the autogenerated release notes.

grafana-plugin/e2e-tests/schedules/schedulesList.test.ts

@@ -10,6 +10,7 @@ test('schedule calendar and list of schedules is correctly displayed', async ({
   await createOnCallSchedule(page, onCallScheduleName, userName);
 
   await goToOnCallPage(page, 'schedules');
+  await page.waitForLoadState('networkidle');
 
   // schedule slots are present in calendar
   const nbOfSlotsInCalendar = await page.getByTestId('schedule-slot').count();

grafana-plugin/package.json

@@ -13,6 +13,7 @@
     "labels:unlink": "pnpm --dir ../../gops-labels/frontend unlink",
     "mage:build-dev": "go mod download && mage -v build:debug",
     "mage:watch": "go mod download && mage -v watch",
+    "mod:download": "go mod download",
     "test-utc": "TZ=UTC jest --verbose --testNamePattern '^((?!@london-tz).)*$'",
     "test-london-tz": "TZ=Europe/London jest --verbose --testNamePattern '@london-tz'",
     "test": "PLUGIN_ID=grafana-oncall-app pnpm test-utc && pnpm test-london-tz",