add tests for invalid strings

[mwetter]

I found in the last two issues quite a few wrong usages of strings, or missing documentation, for example, #1304 and #1306

Running a test in the library gives

*** Error:  File '/Utilities/IO/Files/Examples/JSONWriter.mo' contains invalid string 'Algorithm='.
*** Error:  File '/Utilities/IO/Files/BaseClasses/OutputTime.mo' does not contain required string 'documentation'.
*** Error:  File '/Fluid/HeatPumps/Compressors/BaseClasses/PartialCompressor.mo' contains invalid string 'modelica://https://'.
*** Error:  File '/Fluid/MixingVolumes/Validation/BaseClasses/MixingVolumeReverseFlow.mo' contains invalid string 'modelica://https://'.
*** Error:  File '/Fluid/Sources/TraceSubstancesFlowSource.mo' contains invalid string 'modelica://https://'.
*** Error:  File '/Fluid/HeatExchangers/DryCoilEffectivenessNTU.mo' contains invalid string 'modelica://Buildings'.
*** Error:  File '/Fluid/HeatExchangers/Validation/DryCoilEffectivenessNTU.mo' contains invalid string 'modelica://Buildings'.
*** Error:  File '/Fluid/FixedResistances/Examples/FlowJunction.mo' contains invalid string 'modelica://https://'.
*** Error:  File '/Fluid/FixedResistances/Examples/CheckValve.mo' contains invalid string 'Algorithm='.
*** Error:  File '/Fluid/FixedResistances/Validation/FlowJunctionSteadyState.mo' contains invalid string 'modelica://https://'.
*** Error:  File '/Fluid/FixedResistances/Validation/FlowJunctionSteadyStateNoPressureDrop.mo' contains invalid string 'modelica://https://'.
*** Error:  File '/ThermalZones/ReducedOrder/Validation/RoomWithoutLatentGain.mo' contains invalid string 'Algorithm='.
*** Error:  File '/ThermalZones/ReducedOrder/Validation/RoomWithLatentGain.mo' contains invalid string 'Algorithm='.
*** Error:  File '/ThermalZones/ReducedOrder/Validation/VDI6007/BaseClasses/VerifyDifferenceThreePeriods.mo' contains invalid string 'modelica://https://'.
*** Error:  File '/BoundaryConditions/WeatherData/ReaderTMY3.mo' contains invalid string 'modelica://Buildings'.

This issue is to add such tests as part of the CI testing so these mistakes are caught before they are on the master branch and merged to downstream libraries.