Use ManualParameter instead of Parameter when it's more appropriate

Explanation of changes

The Parameters when initial_cache_value is used must be changed to ManualParameter with initial_value.

Motivation of changes

Sometimes Parameter is used instead of ManualParameter when there is no set_cmd for that parameter. In these cases, the set_cmd is set to False, but that seems incorrect, because qcodes “ignores” the set_cmd when it’s None (not False). Because of this, the original authors used initial_cache_value instead of initial_value to get around this problem. This seems a hacky solution to an incorrectly used qcodes interface.

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Merge checklist

See also merge request guidelines

• Merge request has been reviewed (in-depth by a knowledgeable contributor), and is approved by a project maintainer.
• New code is covered by unit tests (or N/A).
• New code is documented and docstrings use numpydoc format (or N/A).
• New functionality: considered making private instead of extending public API (or N/A).
• Public API changed: added @deprecated and entry in deprecated code suggestions (or N/A).
• Newly added/adjusted documentation and docstrings render properly (or N/A).
• Pipeline fix or dependency update: post in #software-for-developers channel to merge main back in or update local packages (or N/A).
• Tested on hardware (or N/A).
• CHANGELOG.md for breaking changes and AUTHORS.md have been updated (or N/A).
• Update Hardware backends documentation if backend interface change or N/A
• Check whether performance is significantly affected by looking at the Performance metrics results.
• Windows tests in CI pipeline pass (manually triggered by maintainers before merging).
  • Maintainers do not hit Auto-merge, we need to actively check as manual tests do not block pipeline

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For reference, the issues workflow is described in the contribution guidelines.