♻️ Remove POWER from sqlite-dist Calculations (#769)

- Remove the use of POWER from distance calculations to address issue #692
- Replace use of POWER with explicit multiplication.

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Co-authored-by: Shan E Ahmed Raza <13048456+shaneahmed@users.noreply.github.com>

tiatoolbox/annotation/storage.py

@@ -2588,8 +2588,10 @@ def _initialize_query_string_parameters(
             if geometry_predicate == "centers_within_k":
                 # Use rtree index to check distance between points
                 query_string += (
-                    "AND (POWER((:min_x + :max_x)/2 - (min_x + max_x)/2, 2) + "
-                    " POWER((:min_y + :max_y)/2 - (min_y + max_y)/2, 2)) < :distance2 "
+                    "AND (((:min_x + :max_x)/2 - (min_x + max_x)/2)*"
+                    "((:min_x + :max_x)/2 - (min_x + max_x)/2) + "
+                    " ((:min_y + :max_y)/2 - (min_y + max_y)/2)*"
+                    "((:min_y + :max_y)/2 - (min_y+ max_y)/2)) < :distance2 "
                 )
                 query_parameters["distance2"] = distance**2
             # Otherwise, perform a regular bounding box intersection