Encode the pipe character in mbox cookie

The mbox cookie uses a pipe delimiter as follows:

mbox=PC#e03088f9e8cb4e07a5ad1103f49a0b58.17_0#1646387508|session#aef29d047d614042a63ffbdb82b87c06#1583144568;

Some customers have firewalls that block the pipe character in the mbox cookie and requires that the character is encoded.