Refactor subclasses of BaseChangesAuditor to use AuditEvents module

Overview

Due to the Bounded Contexts working group, it's necessary for all Audit Event classes to be nested within AuditEvents, rather than Audit.

Currently, all subclasses of BaseChangesAuditor are nested within the Audit module but config/bounded_contexts.yml suggests that they should be nested within AuditEvents, which is probably correct.

Usually adding a new audit event type will require adding a new subclass of BaseChangesAuditor so this will affect engineers outside of groupcompliance.

Proposed solution

Refactor all subclasses of BaseChangesAuditor to be within the module of their bounded context. e.g. Audit::ProjectAnalyticsChangesAuditor would become Analytics::ProjectAnalyticsChangesAuditor

./ee/lib/audit/project_setting_changes_auditor.rb:  class ProjectSettingChangesAuditor < BaseChangesAuditor
./ee/lib/audit/external_status_check_changes_auditor.rb:  class ExternalStatusCheckChangesAuditor < BaseChangesAuditor
./ee/lib/audit/application_setting_changes_auditor.rb:  class ApplicationSettingChangesAuditor < BaseChangesAuditor
./ee/lib/audit/user_setting_changes_auditor.rb:  class UserSettingChangesAuditor < BaseChangesAuditor
./ee/lib/audit/compliance_framework_changes_auditor.rb:  class ComplianceFrameworkChangesAuditor < BaseChangesAuditor
./ee/lib/audit/group_merge_request_approval_setting_changes_auditor.rb:  class GroupMergeRequestApprovalSettingChangesAuditor < BaseChangesAuditor
./ee/lib/audit/project_ci_cd_setting_changes_auditor.rb:  class ProjectCiCdSettingChangesAuditor < BaseChangesAuditor
./ee/lib/audit/project_changes_auditor.rb:  class ProjectChangesAuditor < BaseChangesAuditor
./ee/lib/audit/group_changes_auditor.rb:  class GroupChangesAuditor < BaseChangesAuditor
./ee/lib/audit/project_feature_changes_auditor.rb:  class ProjectFeatureChangesAuditor < BaseChangesAuditor
./ee/lib/audit/push_rules/group_push_rules_changes_auditor.rb:    class GroupPushRulesChangesAuditor < BasePushRulesChangesAuditor
./ee/lib/audit/push_rules/project_push_rules_changes_auditor.rb:    class ProjectPushRulesChangesAuditor < BasePushRulesChangesAuditor
./ee/lib/audit/push_rules/base_push_rules_changes_auditor.rb:    class BasePushRulesChangesAuditor < BaseChangesAuditor
./ee/lib/audit/protected_branches_changes_auditor.rb:  class ProtectedBranchesChangesAuditor < BaseChangesAuditor
./ee/lib/audit/project_security_setting_changes_auditor.rb:  class ProjectSecuritySettingChangesAuditor < BaseChangesAuditor
./ee/lib/audit/namespace_setting_changes_auditor.rb:  class NamespaceSettingChangesAuditor < BaseChangesAuditor

/cc @fabiopitino