docs: small fixes and tweaks on CLI governance pages

[Ryun1]

Checklist

• [x] I have read the How to Contribute.
• [x] I have run yarn build after adding my changes without getting any errors.
• [x] I have not committed any changes to yarn.lock (or have removed these changes).

Updating documentation or Bugfix

What?

Governance actions page

• Substituting broken links (to my repo) for permalinks based on the CIPs repo
• Updated info around metadata standards, to take into consideration https://github.com/cardano-foundation/CIPs/pull/835
• Fixing typos on governance actions page
• Making the governance actions page more consistent
• Made code blocks use shell consistently

Other Governance CLI Pages

• Fixed typos
• Made code blocks use shell consistently
• Made cardano-cli command indentation consistent

Motivation

@gufmar spotted the CIP108 anchor errors and let me know!

[Ryun1]

Ready for review!

[Ryun1]

@rphair

Good catches! I have amended via af07114.

But I can see the value in standardising on a 2-space indent since in some places here it's unindented and in other places 4 spaces.

I just went with two, as it seemed that two was used the most I don't have strong feelings on it, just wanted to be consistent