Resolves: tdf#96561 Include embedded null-characters while assembling CSV line

... instead of prematurely ending analysis and skipping the
remainder that is still part of data read.

Change-Id: I8f34bc9672e37f9c1c1ae81ddeba464360add7c2
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/120555
Reviewed-by: Eike Rathke <erack@redhat.com>
Tested-by: Jenkins
diff --git a/sc/source/ui/docshell/impex.cxx b/sc/source/ui/docshell/impex.cxx
index f64cf4b..3a798b3 100644
--- a/sc/source/ui/docshell/impex.cxx
+++ b/sc/source/ui/docshell/impex.cxx
@@ -2516,8 +2516,17 @@ Label_RetryWithNewSep:
        while (!rStream.eof() && aStr.getLength() < nArbitraryLineLengthLimit)
        {
            const sal_Unicode * p = aStr.getStr() + nLastOffset;
            while (*p)
            const sal_Unicode * const pStop = aStr.getStr() + aStr.getLength();
            while (p < pStop)
            {
                if (!*p)
                {
                    // Skip embedded null-characters. They don't change
                    // anything and are handled at a higher level.
                    ++p;
                    continue;
                }

                if (nQuotes)
                {
                    if (*p == cFieldQuote)