Update default maximum database connection lifetime.

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## [Unreleased]

### Changed

- Default maximum database connection lifetime is now 1 hour.

### Fixed

- CRON expressions for leaderboard and tournament resets now allow concurrent processing.

// DatabaseConfig is configuration relevant to the Database storage.

type DatabaseConfig struct {

	Addresses         []string `yaml:"address" json:"address" usage:"List of database servers (username:password@address:port/dbname). Default 'root@127.0.0.1:26257'."`

	ConnMaxLifetimeMs int      `yaml:"conn_max_lifetime_ms" json:"conn_max_lifetime_ms" usage:"Time in milliseconds to reuse a database connection before the connection is killed and a new one is created. Default 0 (unlimited)."`

	ConnMaxLifetimeMs int      `yaml:"conn_max_lifetime_ms" json:"conn_max_lifetime_ms" usage:"Time in milliseconds to reuse a database connection before the connection is killed and a new one is created. Default 3600000 (1 hour)."`

	MaxOpenConns      int      `yaml:"max_open_conns" json:"max_open_conns" usage:"Maximum number of allowed open connections to the database. Default 100."`

	MaxIdleConns      int      `yaml:"max_idle_conns" json:"max_idle_conns" usage:"Maximum number of allowed open but unused connections to the database. Default 100."`

}

func NewDatabaseConfig() *DatabaseConfig {

	return &DatabaseConfig{

		Addresses:         []string{"root@127.0.0.1:26257"},

		ConnMaxLifetimeMs: 0,

		ConnMaxLifetimeMs: 3600000,

		MaxOpenConns:      100,

		MaxIdleConns:      100,

	}