[INFRA] Stop automatically announcing new versions on Twitter

[tbouffard]

The last runs of the GH workflow used to announce new releases failed when trying to publish the message to Twitter:

• v0.33.1 on 2023-04-17 https://github.com/process-analytics/bpmn-visualization-js/actions/runs/4719783176/jobs/8371072228 logs_39591.zip
• v0.34.0 on 2023-05-05 https://github.com/process-analytics/bpmn-visualization-js/actions/runs/4891338574/jobs/8731729533 logs_40501.zip
• v0.34.1 on 2023-05-15 https://github.com/process-analytics/bpmn-visualization-js/actions/runs/4979021049/jobs/8910093976 logs_40740.zip
• v0.35.0 on 2023-05-30 https://github.com/process-analytics/bpmn-visualization-js/actions/runs/5122595757/jobs/9211902885
• v0.36.0 on 2023-06-12 https://github.com/process-analytics/bpmn-visualization-js/actions/runs/5243660154/jobs/9468631562
• v0.37.0 on 2023-06-26 https://github.com/process-analytics/bpmn-visualization-js/actions/runs/5378430288/jobs/9758217918
• v0.38.0

Error message Request failed with code 401 - Could not authenticate you. (Twitter code 32)
Both runs use snow-actions/tweet@v1.4.0

Possible cause

Change with the access to the Twitter API:

• https://techcrunch.com/2023/02/01/twitter-to-end-free-access-to-its-api/
• https://arstechnica.com/tech-policy/2023/03/twitter-suffered-embarrassing-api-failure-apparently-breaking-all-links/ on 2023-03-06
• https://www.engadget.com/twitter-shut-off-its-free-api-and-its-breaking-a-lot-of-apps-222011637.html on 2023-04-06

Decision

API not available anymore so remove the publishing of tweet for new release

### Tasks
- [x] Remove the twitter secrets from the repository
- [x] Remove the tweet from the announce workflow
- [x] Update the release procedure to send the tweet manually

Notes

This will probably occur with the announce workflow of https://github.com/process-analytics/bpmn-visualization-R/actions/workflows/announce-new-release.yml --> process-analytics/bpmn-visualization-R#239