Update breaking changes guide with how to use reusable content blocks (…

…airbytehq#68116)

## What
<!--
* Describe what the change is solving. Link all GitHub issues related to
this change.
-->

Updated the guide AJ produced for breaking connector changes. Adds
instructions to use the block of generic connector upgrade information
that can be added dynamically.

## How
<!--
* Describe how code changes achieve the solution.
-->

## Review guide
<!--
1. `x.py`
2. `y.py`
-->

## User Impact
<!--
* What is the end result perceived by the user?
* If there are negative side effects, please list them. 
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## Can this PR be safely reverted and rolled back?
<!--
* If unsure, leave it blank.
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- [x] YES 💚
- [ ] NO ❌

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Co-authored-by: Patrick Nilan <[email protected]>

1.8 release notes (airbytehq#64145)

Rbroughan/productionalize direct loader (airbytehq#61528)

Co-authored-by: Octavia Squidington III <[email protected]>

A quick second pass through the custom components topic (airbytehq#56462

)

airbytehq#11504 v1.5 release notes (airbytehq#53647)

Co-authored-by: Alexandre Cuoci <[email protected]>

airbyte-ci: correct mounted volumes ownership (airbytehq#51582)

v-1.3-release-note (airbytehq#48827)

1.2 release notes (airbytehq#48127)

docs: 1.1.0 release noes (airbytehq#46320)

docs(source-intercom): Update outdated URLs in docs (airbytehq#45858)