feat: update GitLab Workflow extension to v5.17.0

Issue: Register `gitlab.featureFlags.languageServerWeb... (gitlab-vscode-extension#1517 - closed)

What does this MR do and why?

This MR updates the GitLab Workflow extension version to include the changes to add the languageServerWebIDE feature flag.

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

How to set up and validate locally

1. In the gitlab-web-ide project, run git submodule update
2. cd gitlab-vscode-extension
3. Checkout this branch
4. cd .. && yarn run start:example
5. In the network tab of the browser dev tool, inspect the request to /web-ide/public/vscode/extensions/gitlab-vscode-extension/package.json. Should see the two newly added flags gitlab.duoCodeSuggestions.openTabsContext and gitlab.featureFlags.languageServerWebIDE.