CPPIGetOwner is not checked against nil

[DBotThePony]

Example:

wire/lua/wire/client/text_editor/wire_expression2_editor.lua

Line 1466 in f0d26b3

if CPPI and v:CPPIGetOwner():GetName() ~= nick then

Which cause next error:

[Wiremod] lua/wire/client/text_editor/wire_expression2_editor.lua:1466: attempt to index a nil value

1. DoClick - lua/wire/client/text_editor/wire_expression2_editor.lua:1466
2. unknown - lua/vgui/dlabel.lua:253 (x7)

https://gitlab.com/DBotThePony/DLib/-/issues/154

As per CPPI specs, which DPP/2 follows:

Solution should be a simple IsValid(entity:CPPIGetOwner()) call to see if entity is owned by anyone