fix(ownership-differ): standardise ownership change event payload

[ngamanda]

Standardise payload for all ownership related change events to follow the DataHub documentation.

Specifically:

• Adding missing ownerType in the parameters key for all Ownership Change Events
• Updating 'Ownership type has changed' events to use OwnerChangeEvent instead of ChangeEvent

This was discovered while trying to leverage on the DataHub actions to respond to ownership changes. We needed to retrieve both the ownerUrn and ownerType from the action.

Checklist

• The PR conforms to DataHub's Contributing Guideline (particularly Commit Message Format)
• Links to related issues (if applicable)
• Tests for the changes have been added/updated (if applicable)
• Docs related to the changes have been added/updated (if applicable). If a new feature has been added a Usage Guide has been added for the same.
• For any breaking change/potential downtime/deprecation/big changes an entry has been made in Updating DataHub

[github-actions]

Unit Test Results (build & test)

562 tests  ±0   562 ✔️ ±0   12m 50s ⏱️ +3s
139 suites ±0       0 💤 ±0 
139 files   ±0       0 ❌ ±0 

Results for commit ff15e60. ± Comparison against base commit f00e1f4.

♻️ This comment has been updated with latest results.

[jjoyce0510]

This looks great. Thank you!

[jjoyce0510]

Once this passes, will go ahead and merge.