Ensure lockfile is preserved when dumping model

[soapy1]

fixes conda-incubator#986
related to conda-incubator#985

Description

The issue described in conda-incubator#986 is (in part) caused by https://github.com/conda-incubator/conda-store/blob/main/conda-store-server/conda_store_server/_internal/server/views/api.py#L883-L890 where the lockfile spec is loaded into the LockfileSpecification model. When this happens, some of the fields from the lockfile disappear.

This happens here because in updating pydantic the way the model was getting dumped also was updated. Moving from calling the dict function to the model_dump function. For example in https://github.com/conda-incubator/conda-store/pull/985/files#diff-91666c161b2c4e479323a0d582f7ab9198bcc1523739281e191fb433fbb4c69bR85. Usingmodel_dump directly skips using conda-lock's dict_for_output function, which is required for properly dumping the model.

By ensuring that the conda lock dict_for_output is used to dump the LockfileSpecification model, the issue described in conda-incubator#986 is resolved

Pull request checklist

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• Did you add/update relevant tests for this change (if required)?