Fix open dss gql for fixed time

[clydeu]

Description

Fix the graphql query when running opendss export in fixed load time.

Associated tasks

n/a

Test Steps

Explain in detail how your reviewer can test the changes proposed in this PR. If it cannot be tested, leave an explanation on why.

Checklist

If any of these are not applicable, strikethrough the line ~like this~. Do not delete it!. Let the reviewer decide if you should have done it.

Code

• I have performed a self review of my own code (including checking issues raised when creating the PR).
• I have added/updated unit tests for these changes, and if not I have explained why they are not necessary.
• I have commented my code in any hard-to-understand or hacky areas.
• I have handled all new warnings generated by the compiler or IDE.
• I have rebased onto the target branch (usually main).

Documentation

• I have updated the changelog.
• I have updated any documentation required for these changes.

Breaking Changes

• I have considered if this is a breaking change and will communicate it with other team members by posting it on the Slack breaking-changes channel.

not breaking change.

[vincewhite]

Tested and works.

[vincewhite]

Tested working.