Always run the GCodeAnalyser, even if the slicer provided analysis

[eyal0]

The analysis from the Slicer or other sources is sent to the GCodeAnalyser, which can use it or ignore it.

This fixes #2445 (comment)

• 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?

Run GCodeAnalyser on files sliced on RPi, in addition to those uploaded.

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

Without this patch:

1. Run OctoPrint
2. Upload a file.
3. Observe that the file is analyzed (logs will show Starting analysis of <filename>)
4. Slice a file using a built-in slicer, like cura.
5. No logs about analyzing are printing.

With this patch:

1. Run OctoPrint
2. Upload a file.
3. Observe that the file is analyzed (logs will show Starting analysis of <filename>)
4. Slice a file using a built-in slicer, like cura.
5. Observe that the file is analyzed (logs will show Starting analysis of <filename>)

Any background context you want to provide?

This is important for the new analysis hook.
#2445 (comment)

What are the relevant tickets if any?

#2445