Fixed muon fitting bugs

[AnthonyLim23]

A user has reported a couple of bugs in muon analysis. Check that you can cause the bugs on your dev build before testing the fix.

Bug 1:
Open muon analysis
Select the EMU instrument
Load 84447-9 (and repeat with 84447-9)
Go to fitting
Add dynamicKobyeTobye
Fix the field
Tick simultaneous fitting
Change from run to group/pair
Change the field values (all of them should be fixed) to have unique values (e.g. 1,2,3 ...)
Click the increment run button or load current run
CRASH!

Bug 2:
Open muon analysis
Load some data
Go to fitting
Add a function
Manually change a value
Errors have gone

After fix 2, the errors will still disappear, but will come back after doing a fit.

To test:

Fixes #29669.

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Reviewer

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Code Review

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• Does the code conform to the coding standards?
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Functional Tests

• Do changes function as described? Add comments below that describe the tests performed?
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[Matt-Cumber]

Good job fixing both of these bugs 👍 The crash no longer appears and the errors re-appear after fitting.

not ready to merge

[Matt-Cumber]

All tests pass