tests: fix test_page_boxes when verapdf unavailable

The test expected MediaBox preservation for pdfa output, but this only
works when verapdf is available for speculative PDF/A conversion.
Without verapdf (Linux/Windows CI), Ghostscript normalizes the MediaBox.

Also convert pikepdf.Array to list in assertions for clearer error
messages, avoiding pytest repr issues with pikepdf objects.

tests/test_page_boxes.py

@@ -6,6 +6,8 @@ from __future__ import annotations
 import pikepdf
 import pytest
 
+from ocrmypdf._exec import verapdf
+
 from .conftest import check_ocrmypdf
 
 page_rect = [0, 0, 612, 792]
@@ -14,12 +16,14 @@ wh_rect = [0, 0, 412, 592]
 
 neg_rect = [-100, -100, 512, 692]
 
+# When speculative PDF/A succeeds (verapdf available), MediaBox is preserved.
+# Ghostscript would normalize MediaBox to start at origin, but speculative
+# conversion bypasses Ghostscript.
+_pdfa_inset_expected = inset_rect if verapdf.available() else wh_rect
+
 mediabox_testdata = [
-    # When speculative PDF/A succeeds (verapdf available), MediaBox is preserved.
-    # Ghostscript would normalize MediaBox to start at origin, but speculative
-    # conversion bypasses Ghostscript.
-    ('fpdf2', 'pdfa', 'ccitt.pdf', None, inset_rect, inset_rect),
-    ('sandwich', 'pdfa', 'ccitt.pdf', None, inset_rect, inset_rect),
+    ('fpdf2', 'pdfa', 'ccitt.pdf', None, inset_rect, _pdfa_inset_expected),
+    ('sandwich', 'pdfa', 'ccitt.pdf', None, inset_rect, _pdfa_inset_expected),
     ('fpdf2', 'pdf', 'ccitt.pdf', None, inset_rect, inset_rect),
     ('sandwich', 'pdf', 'ccitt.pdf', None, inset_rect, inset_rect),
     (
@@ -68,7 +72,7 @@ def test_media_box(
 
     with pikepdf.open(outdir / 'processed.pdf') as pdf:
         page = pdf.pages[0]
-        assert page.mediabox == crop_expected
+        assert [float(x) for x in page.mediabox] == crop_expected
 
 
 cropbox_testdata = [
@@ -122,4 +126,4 @@ def test_crop_box(
 
     with pikepdf.open(outdir / 'processed.pdf') as pdf:
         page = pdf.pages[0]
-        assert page.cropbox == crop_expected
+        assert [float(x) for x in page.cropbox] == crop_expected