The SDMX Converter tool, when it is used to convert data to "GENERIC_DATA_2_1", produces SDMX which is supposed to be compatible with InputSdmxMl_Structure. However the tool does not assign an ID to the ObsDimension elements. But the InputSdmxMl_Structure class expects them to have an ID of "TIME_PERIOD". This PR removes that expectation, allowing the class to find those ObsDimension elements regardless of their ID.
The SDMX Converter tool, when it is used to convert data to "GENERIC_DATA_2_1", produces SDMX which is supposed to be compatible with InputSdmxMl_Structure. However the tool does not assign an ID to the ObsDimension elements. But the InputSdmxMl_Structure class expects them to have an ID of "TIME_PERIOD". This PR removes that expectation, allowing the class to find those ObsDimension elements regardless of their ID.