Bugfix: Fix "Share on LinkedIn" feature

[stefdworschak]

Possible issues

• Image too big
• Description too long
• Screenshot too big

Examples:

• Working: https://hackathon.codeinstitute.net/showcase/63/
• Not Working: https://hackathon.codeinstitute.net/showcase/67/

Troubleshooting & testing:

• Troubleshooting approach: Create different projects and try to share
• Test this by using the Post Inspector: https://www.linkedin.com/post-inspector/