[docs] Refine and polish out Templates page

[zanivan]

• I have followed (at least) the PR section of the contributing guide.

This PR addresses some items from #41469 :
12. Rename the “landing page” template given it looks more like a home page
14. Allow to click on the image to open it. Uploading Screen Recording 2024-06-10 at 18.14.18.mov…

The changes made were:

• Rename landing-page to marketing-page (that's why there are so many files changed)
• Added some tweaks to templates' page text and title
• Remove outdated files from Pricing and StickyFooter templates
• Added a button to open template preview in the CardImage

[mui-bot]

Netlify deploy preview

• docs/data/material/getting-started/templates/marketing-page/README.md
• docs/data/material/getting-started/templates/templates.md

Bundle size report

No bundle size changes (Toolpad)
No bundle size changes

Generated by 🚫 dangerJS against 28ab395

[zanivan]

@samuelsycamore would you mind doing a pass-through on this page content and also the templates to detect any typos or improvements?

[zanivan]

@siriwatknp I think the Argos test is detecting many screenshots from the marketing page template (old landing page template). Could this be related to the new screenshot script? Otherwise, can I approve the Argos test?

[zanivan]

Just a small bump on this one, I need to merge it to start working on the theme unification and consistency @siriwatknp @DiegoAndai @samuelsycamore

[samuelsycamore]

text looks good to me!

[siriwatknp]

We might need to revisit the regression tests for templates next. I encounter unrelated Argos changes in other PRs from templates (especially with charts) multiple times.