Refactor the StreamClassRepository class

[s-vitaliy]

Part of #24

Scope

Implemented:

• Refactored the StreamDefinitionRepository class to use asyncrchonious API
• Fixed return type of the IStreamClassRepository.Get method

Additional changes:

• Added the AsOptionalStreamDefinition extension method to avoid code duplication and unnecessary type casts

Checklist

• GitHub issue exists for this change.
• Unit tests added and they pass.
• Line Coverage is at least 80%.
• Review requested on latest commit.

[github-actions]

Coverage after merging refactor-stream-definition-repository into main will be

53.33%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
src
ArcaneEnvironment.cs	0%	100%	0%	0%	10, 5, 8–9
src/Extensions
JsonElementExtensions.cs	0%	100%	0%	0%	20
V1JobExtensions.cs	85.58%	75%	90.91%	90.16%	40, 40, 45, 61–62, 62, 62, 62, 62–65, 83, 83
src/Models/StreamClass
V1Beta1StreamClassSpec.cs	20%	100%	20%	20%	11, 17, 23, 29
src/Models/StreamClass/Base
IStreamClass.cs	0%	100%	0%	0%	44–49
src/Models/StreamDefinitions/Base
IStreamDefinition.cs	90%	83.33%	100%	100%	28
src/Models/StreamStatuses/StreamStatus/V1Beta1
V1Beta1StreamStatus.cs	100%	100%	100%	100%
src/Services
StreamInteractionService.cs	0%	100%	0%	0%	16–19, 23–27, 31–35, 39–45
src/Services/Maintenance
HostedStreamingJobMaintenanceService.cs	0%	0%	0%	0%	16–24, 27–29, 29, 29–36, 39–42
StreamingJobMaintenanceService.cs	89.84%	82.14%	100%	91.40%	103–106, 121, 130–133, 135, 61, 66, 97
src/Services/Operator
HostedStreamOperatorService.cs	82.14%	100%	66.67%	82.61%	39–42
StreamClassOperatorService.cs	70.30%	40%	75%	73.49%	107–110, 116, 121–122, 127–130, 74, 74, 77, 79, 84–86, 86, 86–91, 97–99
StreamOperatorService.cs	93.47%	87.04%	100%	95.65%	105–111, 116, 124, 138, 138, 144, 166
StreamOperatorServiceWorker.cs	77.78%	50%	75%	80%	47–51, 56, 64
StreamOperatorServiceWorkerFactory.cs	100%	100%	100%	100%
src/Services/Repositories
StreamDefinitionRepository.cs	0%	0%	0%	0%	100–111, 22–29, 32–34, 34, 34–49, 53–55, 55, 55–76, 79–81, 81, 81–93, 96–98, 98, 98–99
StreamingJobTemplateRepository.cs	0%	0%	0%	0%	20–27, 31–33, 33, 33, 33, 33, 33, 33, 33, 33–36, 39–47
src/Services/Streams
StreamingJobOperatorService.cs	0%	0%	0%	0%	100–107, 110–113, 113, 113–115, 118–121, 121, 121–123, 126–129, 129, 129–131, 134–137, 140–146, 150–152, 152, 152, 152, 152–155, 155, 155, 155, 155–156, 158–161, 163–169, 173, 173, 173, 173, 173–179, 182–188, 191–200, 31–43, 46, 49–56, 59–60, 60, 60–63, 63, 63–70, 70, 70–90, 90, 90, 90, 90–93, 93, 93–99