Bug: Executive returns 0 priority instead of priority from constraint checker

[JoshOrndorff]

Constraint checkers have the ability to provide a priority. While many of them currently return 0, the money one returns a useful value. The executive currently fails to use this priority:

Tuxedo/tuxedo-core/src/executive.rs

Lines 161 to 168 in 1ad2343

	// Return the valid transaction
	Ok(ValidTransaction {
	requires: Vec::new(),
	provides,
	priority: 0,
	longevity: TransactionLongevity::max_value(),
	propagate: true,
	})