Actually use setting_version to get the setting version number

This was sort of hidden because we've always incremented the normal version number up until now.

Contributes to issue CURA-3427.

plugins/VersionUpgrade/VersionUpgrade21to22/VersionUpgrade21to22.py

@@ -250,7 +250,7 @@ class VersionUpgrade21to22(VersionUpgrade):
         parser = configparser.ConfigParser(interpolation = None)
         parser.read_string(serialised)
         format_version = int(parser.get("general", "version")) #Explicitly give an exception when this fails. That means that the file format is not recognised.
-        setting_version = int(parser.get("general", "version", fallback = 0))
+        setting_version = int(parser.get("general", "setting_version", fallback = 0))
         return format_version * 1000000 + setting_version
 
     ##  Gets the fallback quality to use for a specific machine-variant-material

plugins/VersionUpgrade/VersionUpgrade22to24/VersionUpgrade.py

@@ -146,5 +146,5 @@ class VersionUpgrade22to24(VersionUpgrade):
         parser = configparser.ConfigParser(interpolation = None)
         parser.read_string(serialised)
         format_version = int(parser.get("general", "version")) #Explicitly give an exception when this fails. That means that the file format is not recognised.
-        setting_version = int(parser.get("general", "version", fallback = 0))
+        setting_version = int(parser.get("general", "setting_version", fallback = 0))
         return format_version * 1000000 + setting_version

plugins/VersionUpgrade/VersionUpgrade25to26/VersionUpgrade25to26.py

@@ -35,7 +35,7 @@ class VersionUpgrade25to26(VersionUpgrade):
         parser = configparser.ConfigParser(interpolation = None)
         parser.read_string(serialised)
         format_version = int(parser.get("general", "version")) #Explicitly give an exception when this fails. That means that the file format is not recognised.
-        setting_version = int(parser.get("general", "version", fallback = 0))
+        setting_version = int(parser.get("general", "setting_version", fallback = 0))
         return format_version * 1000000 + setting_version
 
     ##  Upgrades the preferences file from version 2.5 to 2.6.