Update upgrade path recommendations

What does this MR do?

Updates our upgrade path recommendations with:

• examples using newer supported versions
• note to suggest upgrading only 1 minor version between major versions (11 -> 12 should be 11.11.8 -> 12.0.x) to ensure background migrations are successful before moving on.

Surfaced in slack: @cody @tpresa

Confirmed by @marin in thread

@jcolyer and @WarheadsSE seem to agree with suggesting 11.11.x -> 12.0.x -> 12.x.x

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content