Add missing Manchester picture

### Link to the page

https://codeyourfuture.github.io/github_issues_prs_practice/

### Steps to reproduce

1. Navigate to the website
2. The image for Manchester , on the second row, is missing

Open the linked website and inspect the repository files that assemble the page and its city images. Start by locating the second-row Manchester entry and comparing it with the surrounding entries. Done means the Manchester picture appears on the page in the expected position.

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