Fix Off-By-One Stack Buffer Overflows in XML Parser (#1717)

* Off-By-One Null Byte Fix

* Add XML parser tests and improve XmlGetAttributeText handling

* Refactor XML testing: integrate XmlTest into AutoTestAlgorithms, add sentinel test for XmlGetNodeText insuficient output size.

* Remove no-op Tests.c change

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Co-authored-by: Mounir IDRASSI <mounir.idrassi@amcrypto.jp>

src/Common/Xml.h

@@ -21,6 +21,10 @@ char *XmlGetNodeText (char *xmlNode, char *xmlText, int xmlTextSize);
 char *XmlFindElementByAttributeValue (char *xml, char *nodeName, const char *attrName, const char *attrValue);
 char *XmlQuoteText (const char *textSrc, char *textDst, int textDstMaxSize);
 
+#if !defined(TC_WINDOWS_DRIVER) && !defined(_UEFI)
+BOOL XmlTest (void);
+#endif
+
 #if !defined(_UEFI)
 wchar_t *XmlQuoteTextW(const wchar_t *textSrc, wchar_t *textDst, int textDstMaxSize);
 int XmlWriteHeader (FILE *file);