add unit test and small fixes

theodolite/examples/operator/example-benchmark.yaml

theodolite/examples/operator/example-execution.yaml

.../main/kotlin/theodolite/benchmark/ConfigMapResourceSet.kt

...main/kotlin/theodolite/benchmark/FileSystemResourceSet.kt

...c/main/kotlin/theodolite/benchmark/KubernetesBenchmark.kt

...olite/src/main/kotlin/theodolite/benchmark/ResourceSet.kt

...lite/src/main/kotlin/theodolite/benchmark/ResourceSets.kt

...e/src/main/kotlin/theodolite/k8s/CustomResourceWrapper.kt

...kotlin/theodolite/k8s/resourceLoader/K8sAbstractLoader.kt

...kotlin/theodolite/k8s/resourceLoader/K8sResourceLoader.kt

...t/kotlin/theodolite/benchmark/ConfigMapResourceSetTest.kt

.../kotlin/theodolite/benchmark/FileSystemResourceSetTest.kt

theodolite/src/test/kotlin/theodolite/benchmark/bugReport.kt

...c/test/resources/k8s-resource-files/test-execution-1.yaml