RDISCROWD-7968 add n_gold_tasks to projectprogress API

[n00rsy]

Issue number of the reported bug or feature request: RDISCROWD-7968

Describe your changes
Add n_gold_tasks to /project/<id>/projectprogress API response
No changes to existing fields n_completed_tasks and n_tasks

Example:

Request:
GET /api/project/50/projectprogress

Response:

{
    "n_completed_tasks": 1,
    "n_tasks": 149,
    "n_gold_tasks": 2
}

Testing performed
Tested locally

[coveralls]

Pull Request Test Coverage Report for Build 13420338534

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 2 of 2 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 94.153%

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Totals
Change from base Build 13395416999:	0.0%
Covered Lines:	17585
Relevant Lines:	18677

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💛 - Coveralls

[kbecker42]

Could this query be optimized to a single statement to obtain the counts?

SELECT  
    SUM(CASE WHEN task.state = 'completed' THEN 1 ELSE 0 END) AS n_completed,  
    SUM(CASE WHEN calibration != 1 THEN 1 ELSE 0 END) AS n_tasks,  
    SUM(CASE WHEN calibration = 1 THEN 1 ELSE 0 END) AS n_gold_tasks  
FROM task  
WHERE task.project_id = :project_id;  

[n00rsy]

great suggestion! Implemented in f49f7e7