Maintenance Issue #2077

[galamdring]

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• Your changes are not possible to do through a plugin and relevant
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---

What does this PR do and why is it necessary?

Corrects Issue #2077 caused by the temperature graph only watching Tool0 when Shared Nozzle is enabled, but Comm assigned the temperature it gets to the current tool.

How was it tested? How can it be tested by the reviewer?

     -- Tested with Shared nozzle on, and off. Temp(actual and target) were assigned to Tool0 correctly when SharedNozzle was enabled, and only to the current tool when it was not. 
     -- I was unable to test with multiple temps coming from the firmware, but with the behavior I witnessed, I feel confident that it does not break that functionality.

Any background context you want to provide?

What are the relevant tickets if any?

Issue #2077

Screenshots (if appropriate)

Further notes

[foosel]

Thank you! 👍