Fix english strings consistency (#8881)

* "non zero" -> "non-zero"

* "Z hop" -> "Z-hop"

* "works" -> "is working"

* "version at least x" -> "version x or higher"

* "printing job" -> "print job"
"to print on" -> "printing on"

* "is not find" -> "was not found"

* "boundary of plate" -> "plate boundaries"

* "toolchange" -> "tool change"

* "colour" -> "color"

* "cancelled" -> "canceled"

* "can not" -> "cannot"

* "gcode" -> "G-code"

src/slic3r/Utils/Flashforge.cpp

@@ -58,7 +58,7 @@ bool Flashforge::test(wxString& msg) const
     return res;
 }
 
-wxString Flashforge::get_test_ok_msg() const { return _(L("Serial connection to Flashforge works correctly.")); }
+wxString Flashforge::get_test_ok_msg() const { return _(L("Serial connection to Flashforge is working correctly.")); }
 
 wxString Flashforge::get_test_failed_msg(wxString& msg) const
 {