Allow independent scrolling in split-column mode

[maskeynihal]

Type of Change

• Something else: Add independent scrolling

What issue does this relate to?

resolves https://github.com/digitalocean/nginxconfig.io/issues/430

What should this PR do?

• Add style overflowY: auto and height: 100vh for each column so that it can be scrolled horizontally.

What are the acceptance criteria?

• Independent scrolling should be allowed for each column on Side-by-side mode.

Before

https://github.com/digitalocean/nginxconfig.io/assets/26411488/f0858305-6089-40f7-aeef-c2aba6f97eac

After

https://github.com/digitalocean/nginxconfig.io/assets/26411488/c0d9eb34-388f-4ecb-855a-b67c487d6ef2

[maskeynihal]

@MattIPv4 What should we do for "Back to top" button?

[MattIPv4]

What should we do for "Back to top" button?

Good question -- what do you think would be the best UX? I'm thinking it should scroll the document, and both the columns, back to the top?

[maskeynihal]

@MattIPv4 I have updated the copyright year to 2023.

Should I update the copyright year on every file of the whole repo?

[maskeynihal]

What should we do for "Back to top" button?

Good question -- what do you think would be the best UX? I'm thinking it should scroll the document, and both the columns, back to the top?

Yes, that sounds right. Should I do that in this PR or in another PR?

[MattIPv4]

Should I update the copyright year on every file of the whole repo?

Only the files you have touched in this PR, please

Yes, that sounds right. Should I do that in this PR or in another PR?

It'd be great to do it in this PR, please, as it's related to the change being made here

[maskeynihal]

@MattIPv4 I have updated the code. Now, the independent column also scrolls when "Back to top" is clicked.