Core Unlocked Package Changes

Fixed #538 by changing LogEntryEventHandler to always save LogEntryEvent__e records when LoggerSettings__c.DefaultPlatformEventStorageLoggingLevel__c is null. Thanks to @arbokrad for reporting this issue (and patience, as it's taken about a year to get this fixed 🙃 )
- When previously using the user's logging level from LoggerSettings__c.LoggingLevel__c as a fallback value, it could result in entries being lost if a matching LoggerScenarioRule__mdt exists with a lower logging level
Fixed some unreported issues in Logger with setScenario(String) and endScenario(String) not properly updating the field values returned by getUserSettings()
- Now, both setScenario(String) and endScenario(String) wipe out & reload the in-memory instance of LoggerSettings__c (before applying any matching LoggerScenarioRule__mdt records) to ensure that there are not any remnants lingering when multiple LoggerScenarioRule__mdt records have been applied to the user's settings in a single transaction

Installation Info

SF CLI: sf package install --wait 20 --security-type AdminsOnly --package 04t5Y0000015oFjQAI
SFDX CLI: sfdx force:package:install --wait 20 --securitytype AdminsOnly --package 04t5Y0000015oFjQAI
Sandbox: https://test.salesforce.com/packaging/installPackage.apexp?p0=04t5Y0000015oFjQAI
Production: https://login.salesforce.com/packaging/installPackage.apexp?p0=04t5Y0000015oFjQAI