Use RunWidget in Indirect Simulations interface

Description of work

This PR ensures the new RunWidget is used in the Indirect Simulations interface.

Part of #37381

To test:

Interfaces->Indirect->Simulations
Without loading data, click "Run". A validation message should appear. The Run button should remain enabled.
Load the data below for the relevant tab
Click Run and wait. When running, the Run button should be disabled and say "Running..."
When Running has finished, the Run button should be re-enabled
Click Plot or Plot Result in the output options to make sure external plots appear.

MolDyn: Input File: NaF_DISF.zip FunctionNames: Sqw-Na

Sassena: No data could be found as this is a largely unused tab - so ignore this tab

DensitiesOfStates: Input File: csd_benzen11_PhonDisp.zip

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Functional Tests

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mantidproject / mantid