[TASK] Split up "initialCount" optimization settings input

[GabrielSoto-INL]

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Issue Description

Is your feature request related to a problem? Please describe.
There is a subnode for <optimization_settings> called initialCount which behaves one way if using GradientDescent (modifies the number of trajectories) and another way for BayesianOpt (modifies the number of initial samples). These should be separate.

Describe the solution you'd like
A solution would be to add new inputs under each respective <algorithm> in <optimization_settings> and remove the initialCount input. These could be something like <initialSampleCount> for BayesianOpt and <numTrajectories> for GradientDescent.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

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For Change Control Board: Issue Review

This review should occur before any development is performed as a response to this issue.

• 1. Is it tagged with a type: defect or task?
• 2. Is it tagged with a priority: critical, normal or minor?
• 3. If it will impact requirements or requirements tests, is it tagged with requirements?
• 4. If it is a defect, can it cause wrong results for users? If so an email needs to be sent to the users.
• 5. Is a rationale provided? (Such as explaining why the improvement is needed or why current code is wrong.)

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For Change Control Board: Issue Closure

This review should occur when the issue is imminently going to be closed.

• 1. If the issue is a defect, is the defect fixed?
• 2. If the issue is a defect, is the defect tested for in the regression test system? (If not explain why not.)
• 3. If the issue can impact users, has an email to the users group been written (the email should specify if the defect impacts stable or master)?
• 4. If the issue is a defect, does it impact the latest release branch? If yes, is there any issue tagged with release (create if needed)?
• 5. If the issue is being closed without a pull request, has an explanation of why it is being closed been provided?