fix page index starting from 0 (#4178)(patch)

## Description
Adds adjustment to the offset of the sample querying taking into account that the page number received starts from 1 (not from 0)

cg/services/web_services/sample/service.py

@@ -51,7 +51,7 @@ def get_samples(self, request: SamplesRequest, user: User) -> tuple[list[dict],
             pattern=request.enquiry,
             customers=customers,
             limit=request.page_size,
-            offset=request.page,
+            offset=(request.page - 1) * request.page_size,
         )
         parsed_samples: list[dict] = [sample.to_dict() for sample in samples]
         return parsed_samples, total