Links in README lead to "404 Not Found" pages

[ThesllaDev]

First of all, I would like to congratulate you on the project! I came across it while looking for projects to contribute to during Hacktoberfest, and while reading about it, I found two links in the README file that lead to "404 Not Found" pages. These links need to be reviewed or updated. Below are the details:

"Header" - Located in the Components section - Application UI, currently pointing to this URL. The issue here is just a typo in the URL, where adding the letter "s" will correctly redirect to the right page This URL! .

"Collection Cards" - Located in the Components section - Marketing, currently pointing to this URL. In this case, the page and components don’t seem to exist, so this link might need to be removed.

I would like to work on fixing this issue, but I haven't opened a PR directly to follow the process according to the contribution guide.