Improve code samples expand/collapse

[mDuo13]

After some recent updates, code blocks that aren't part of the code tabs don't seem to be expandable/collapsible anymore. Also, there are some sneaky edge cases in code tabs to keep an eye on with any changes.

Test cases:

• https://xrpl.org/xrp-ledger-toml.html#contents
• https://xrpl.org/signerlist.html
• https://xrpl.org/account_objects.html#response-format
• https://xrpl.org/account_tx.html#request-format

Ideally:

• Code blocks that are small enough to not need to expand won't have an expand/collapse button.
• Expand/collapse work the same way in code tabs and not in tabs
• The Expand/collapse and copy/paste buttons don't overlap the text content.
• Expand/collapse allows a block to expand both vertically and horizontally
• The print CSS shows all code samples fully expanded and with the tabs before each sample.

[mDuo13]

Redocly doesn't support expand/collapse at all, so this is irrelevant now.