Fixed name of VDS chunk metadata key since it was changed not to have hyphens...

Fixed name of VDS chunk metadata key since it was changed not to have hyphens (kebab-case) because it is not valid for Azure BLOB storage metadata keys.

src/VDS/VolumeDataAccessManagerImpl.h

@@ -49,7 +49,7 @@ public:
 
   void handleMetadata(const std::string& key, const std::string& header) override
   {
-    if (key == "vds-chunk-metadata")
+    if (key == "vdschunkmetadata")
     {
       if (!Base64Decode(header.data(), (int)header.size(), m_metadata))
       {