Revert "Check against concrete expected values in PdfExportTest::testTdf115262"

This reverts commit 3bb64c0b, at least Jenkins'
lo_tb_master_win builds started to fail with

> C:/cygwin/home/tdf/lode/jenkins/workspace/lo_tb_master_win/vcl/qa/cppunit/pdfexport/pdfexport.cxx(1581) : error : Assertion
> Test name: `anonymous namespace'::PdfExportTest::testTdf115262
> equality assertion failed
> - Expected: 199
> - Actual  : 198

(<https://ci.libreoffice.org/job/lo_tb_master_win/19796/>).

vcl/qa/cppunit/pdfexport/pdfexport.cxx

@@ -1577,8 +1577,8 @@ void PdfExportTest::testTdf115262()
     }
     // Make sure that the top of the "400" is below the top of the image (in
     // bottom-right-corner-based PDF coordinates).
-    CPPUNIT_ASSERT_EQUAL(232, nFirstImageTop);
-    CPPUNIT_ASSERT_EQUAL(199, nRowTop);
+    // This was: expected less than 144, actual is 199.
+    CPPUNIT_ASSERT_LESS(nFirstImageTop, nRowTop);
     FPDFText_ClosePage(pTextPage);
 }