fix: remove invalid secrets condition in e2e-linux workflow

Removes the invalid `if: ${{ secrets.BOT_APP_ID != '' }}` condition that caused workflow validation to fail. Secrets cannot be checked in if expressions in GitHub Actions.

Also removes the `|| github.token` fallback to require the bot token, making the e2e-linux job consistent with all other jobs in the workflow.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: timvw

.github/workflows/ci.yml

@@ -370,7 +370,6 @@ jobs:
     steps:
       - name: Generate GitHub App token
         id: generate-token
-        if: ${{ secrets.BOT_APP_ID != '' }}
         uses: actions/create-github-app-token@v1
         with:
           app-id: ${{ secrets.BOT_APP_ID }}
@@ -379,7 +378,7 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v4
         with:
-          token: ${{ steps.generate-token.outputs.token || github.token }}
+          token: ${{ steps.generate-token.outputs.token }}
 
       - name: Set up Go
         uses: actions/setup-go@v5