[refactor] deprecate db/common/role.DatabaseRoleMatchers

[greedy52]

pre-req for MongoDB auto-user provisioning change #33717

Changes:

• Removed role.DatabaseRoleMatchers
• Added a new DisableDatabaseNameMatcher flag to role.RoleMatchersConfig
• Refactored the logic of role.GetDatabaseRoleMatchers a little bit and added UT

No backporting necessary.

[Tener]

In theory one may forget to supply one of (db, db user, db name) as these are now optional fields in the config. In practice I think this is unlikely.

[Tener]

I think we should update EnumerateDatabaseUsers to be aware of auto-provisioning, but perhaps this can be a separate PR.

teleport/lib/services/access_checker.go

Lines 565 to 574 in 93e6ec6

	// EnumerateDatabaseUsers specializes EnumerateEntities to enumerate db_users.
	func (a *accessChecker) EnumerateDatabaseUsers(database types.Database, extraUsers ...string) EnumerationResult {
	listFn := func(role types.Role, condition types.RoleConditionType) []string {
	return role.GetDatabaseUsers(condition)
	}
	newMatcher := func(user string) RoleMatcher {
	return NewDatabaseUserMatcher(database, user)
	}
	return a.EnumerateEntities(database, listFn, newMatcher, extraUsers...)
	}

[greedy52]

I think we should update EnumerateDatabaseUsers to be aware of auto-provisioning, but perhaps this can be a separate PR.

teleport/lib/services/access_checker.go

Lines 565 to 574 in 93e6ec6

	// EnumerateDatabaseUsers specializes EnumerateEntities to enumerate db_users.
	func (a *accessChecker) EnumerateDatabaseUsers(database types.Database, extraUsers ...string) EnumerationResult {
	listFn := func(role types.Role, condition types.RoleConditionType) []string {
	return role.GetDatabaseUsers(condition)
	}
	newMatcher := func(user string) RoleMatcher {
	return NewDatabaseUserMatcher(database, user)
	}
	return a.EnumerateEntities(database, listFn, newMatcher, extraUsers...)
	}

Good call. Will do a separate fix.