KNOWN_BUGS: SMB tests fail with Python 2

Reported-by: Jay Satiro
Closes #5983

docs/KNOWN_BUGS

@@ -57,6 +57,7 @@ problems may have been fixed or changed somewhat since this was written!
  5.7 Visual Studio project gaps
  5.8 configure finding libs in wrong directory
  5.9 Utilize Requires.private directives in libcurl.pc
+ 5.10 SMB tests fail with Python 2
  5.11 configure --with-gssapi with Heimdal is ignored on macOS
  5.12 cmake: support build with GnuTLS
  5.13 cmake: unusable tool_hugehelp.c with MinGW
@@ -462,6 +463,12 @@ problems may have been fixed or changed somewhat since this was written!
 
  https://github.com/curl/curl/issues/864
 
+5.10 SMB tests fail with Python 2
+
+ The error message says "TreeConnectAndX not found".
+
+ See https://github.com/curl/curl/issues/5983
+
 5.11 configure --with-gssapi with Heimdal is ignored on macOS
 
  ... unless you also pass --with-gssapi-libs