Add abbott to task page

Author: jluethi

tasks_data_retrieval/sources.txt

@@ -6,3 +6,4 @@ https://github.com/fractal-analytics-platform/fractal-helper-tasks
 https://github.com/fmi-basel/gliberal-scMultipleX
 https://github.com/m-albert/fractal-ome-zarr-hcs-stitching
 https://github.com/pelkmanslab/abbott
+https://github.com/Apricot-Therapeutics/APx_fractal_task_collection