feat: load spec resources from directory

[saig0]

Description

Extend the @BpmnSpecSource annotation for JUnit to accept a directory that contains the spec resources. This is an alternative to the specification of all spec resources explicitly.

@BpmnSpecRunner
class BpmnSpecExtensionTest(private val specRunner: SpecRunner) {

    @ParameterizedTest
    @BpmnSpecSource(specDirectory = "specs")
    fun `should run all specs in directory`(spec: BpmnSpecTestCase) {

        val testResult =
            specRunner.runSingleTestCase(resources = spec.resources, testcase = spec.testCase)

        assertThat(testResult).isSuccessful()
    }

}