fix: page_number for pdfs with pages not containing any text

.github/workflows/rest_api_tests.yml

@@ -110,7 +110,7 @@ jobs:
       - name: Install REST API
         run: |
           pip install -U "./rest_api[dev]"
-          pip install ".[inference,dev]"
+          pip install ".[inference,dev,preprocessing]"
           pip install .
 
       - name: Run tests

VERSION.txt

@@ -1 +1 @@
-1.25.0-rc0
+1.25.0-rc1

haystack/nodes/preprocessor/preprocessor.py

@@ -641,6 +641,9 @@ def _concatenate_units(
                     else:
                         num_page_breaks = len(processed_units)
                     cur_page += num_page_breaks
+            else:
+                if self.add_page_number and split_at == "\f":
+                    cur_page += 1
 
         return text_splits, splits_pages, splits_start_idxs