Resolves: tdf#92448 check for numeric '.' only if sheet separator is '.'

Change-Id: I427da08eed3fc5daed2bac4d588b66a3f03fd28c
(cherry picked from commit 2fd3560e)
Reviewed-on: https://gerrit.libreoffice.org/17244Reviewed-by: Markus Mohrhard <markus.mohrhard@googlemail.com>
Tested-by: Markus Mohrhard <markus.mohrhard@googlemail.com>

sc/source/core/tool/compiler.cxx

@@ -2929,7 +2929,7 @@ bool ScCompiler::IsReference( const OUString& rName )
     if ( ch1 == cDecSep )
         return false;
     // Who was that imbecile introducing '.' as the sheet name separator!?!
-    if ( rtl::isAsciiDigit( ch1 ) )
+    if ( rtl::isAsciiDigit( ch1 ) && pConv->getSpecialSymbol( Convention::SHEET_SEPARATOR) == '.' )
     {
         // Numerical sheet name is valid.
         // But English 1.E2 or 1.E+2 is value 100, 1.E-2 is 0.01