Move muon HDF4 loaders to Framework/Muon library

[robertapplin]

Description of work

This PR moves the LoadMuonNexus1 and LoadMuonNexus2 algorithms to the Framework/Muon library instead of Framework/DataHandling. These two algorithms are the only algorithms in Mantid used to load HDF4 Nexus files. The plan is to isolate these two algorithms within the Framework/Muon library, and then convert the code to use the HDF4 API directly instead of the Nexus API.

We want to remove the Nexus API for several reasons:

• It is unsupported and has been unsupported for a number of years
• We want to consolidate the ways in which we load nexus data into Mantid - and to do this we ultimately want a lightweight wrapper library around the HDF5 API, instead of using the current Nexus wrapper library and Nexus API we use.
• Removing the use of Nexus API in favour of HDF5 API might have some speed benefits

Part of #38214

To test:

Complete the Muon Analysis test guide without issue
https://developer.mantidproject.org/Testing/MuonAnalysis_test_guides/index.html

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[robertapplin]

No longer needed, going in a different direction