Revert the update of the 7-Zip property sizes

- change the 7-Zip property size for LZ4, LZ5 and Zstandard back to 5
- the code understands 3 and 5 bytes, but we default to 5 ...

CPP/7zip/Compress/Lz4Encoder.h

@@ -29,6 +29,7 @@ struct CProps
   Byte _ver_major;
   Byte _ver_minor;
   Byte _level;
+  Byte _reserved[2];
 };
 
 class CEncoder:

CPP/7zip/Compress/Lz5Encoder.h

@@ -29,6 +29,7 @@ struct CProps
   Byte _ver_major;
   Byte _ver_minor;
   Byte _level;
+  Byte _reserved[2];
 };
 
 class CEncoder:

CPP/7zip/Compress/ZstdEncoder.h

@@ -28,6 +28,7 @@ struct CProps
   Byte _ver_major;
   Byte _ver_minor;
   Byte _level;
+  Byte _reserved[2];
 };
 
 class CEncoder: