Fix invalid range

In octal numbering system only the digits 0-7 are valid.

Author: skacurt

Rubberduck.Parsing/Grammar/VBALexer.g4

@@ -250,7 +250,7 @@ R_SQUARE_BRACKET : ']';
 L_BRACE : '{';
 R_BRACE : '}';
 STRINGLITERAL : '"' (~["\r\n] | '""')* '"';
-OCTLITERAL : '&O' [0-8]+ INTEGERTYPESUFFIX?;
+OCTLITERAL : '&O' [0-7]+ INTEGERTYPESUFFIX?;
 HEXLITERAL : '&H' [0-9A-F]+ INTEGERTYPESUFFIX?;
 FLOATLITERAL :
     FLOATINGPOINTLITERAL FLOATINGPOINTTYPESUFFIX?