Full export will output invalid Guids in the property data if part of the Guid only contains digits

[rpteasolutions]

Describe the bug
This was found using the Umbraco.ContentPickerAlias and trying to export content. If there is picked a node, data in database will be the node id. uSync changes this to Guid, but if the node guid contains a part with only digits, that part will be converted too, making the guid invalid.
Example 1:
Node id: 4267
Node Guid: 0fb61ac2-b30f-4417-b494-1991a8f704c8
Exported Guid: 0fb61ac2-b30f-bbe793ec-e5f7-43db-8f24-eae947ceb1e6-b494-1991a8f704c8

Example 2:
Node id: 5021
Node Guid: b87b0782-060e-411c-9097-4dc641bbab0a
Exported Guid: b87b0782-060e-411c-0d41897e-efc2-4741-b26c-e035e93afa8c-4dc641bbab0a

To Reproduce
Steps to reproduce the behavior:

1. Create a node that gets a Guid where a part of it is only digits. Eg. aaaaaaaa-1111-aaaa-aaaa-aaaaaaaa
2. Pick the node with a property using the ContentPickerAlias datatype
3. Go to uSync dashboard and do a "Full Export"
4. Look up the exported file and find the value of the property. Should contain an invalid Guid.

Expected behavior
I would expect the export to not trying and convert parts of the node Guid.

About your Site (please complete the following information):

• Umbraco Version: 7.15.2
• uSync Version: 4.0.16
• uSync.ContentEdition Version: 4.1.9.1
• uSync.ContentMappers Version: 4.1.9
• uSync.Core: 6.0.15

Additional context
Discovered this while running uSync migration imports.