the doc of pipeline creation by api is innacurate

In the parameter variables, we should read

[{ 'key': 'UPLOAD_TO_S3', 'variable_type': 'file', 'value': 'true' }]

instead of

[{ 'key' => 'UPLOAD_TO_S3', 'variable_type' => 'file', 'value' => 'true' }]

This invalid json is quite confusing at first. I had to search a bit to confirm the doc was in error

Hope it will save some time for future pipeliners!