Initial work

[duncangrant]

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Adds these resaources:

• Dynatrace::Configuration::Dashboard
• Dynatrace::Environment::Metric
• Dynatrace::Environment::ServiceLevelObjective
• Dynatrace::Environment::SyntheticLocation
• Dynatrace::Environment::SyntheticMonitor

[gsurbhi]

@tbouron Were you able to verify if all the contract tests passed?

[tbouron]

@gsurbhi Yes, they do pass for all resources