fix: anchor links top scroll

[dgarcia360]

Closes #889

Related issue scylladb/scylladb#15420

Handles top scroll padding at the html level (full page) instead of per component type (e.g. sections, glossary).

How to test

1. Build docs

2. Click on any anchor link:

   

3. It should scroll after the header + 10px.

[annastuchlik]

When I click a heading, it looks as expected:

When I click some anchor links, they also look as expected:

But when I click some other links, the heading and some following lines are hidden by the page header.
Example 1. When I click this "make preview" link:

it takes me to:

Example 2. Clicking the "Build previews only (. . .)" link:

opens:

[dgarcia360]

Thanks for reviewing @annastuchlik!

Unfortunately, I wasn't able to replicate the issues on my end:

• When I click the "make preview" link:

• Clicking the "Build previews only (. . .)" link:

It's possible that this could be a cache-related problem. Could you please clear your browser cache and give it another try?

If the issue persists, we can walk through the steps during our next call to try and reproduce the error.

[annastuchlik]

@dgarcia360 I've cleaned everything of everything :) And now it works. Thank you.

[annastuchlik]

LGTM