Require branches to be up to date before merging across all repositories

[kernelsam]

NOTE: This only applies to community repositories: senzing, senzing-garage, senzing-factory

Improve confidence in our status checks

The more automation and gate checks we add for testing prs being merged, the more important it is going to become that we are testing against the latest changes in the main branch.

Enabling allow auto merge might make this a little easier on the dev team so they can basically set it and forget it (if the checks are successful). We already use enable auto merge on repositories that are auto merging dependabot minor version updates.
Email notifications can be configured per developer in github settings to receive notifications on failed pr status checks.
Improvements to slack notifications for failing builds may also alleviate pain points here for developers managing failing builds. Tracked in: #67

Ex.