Guake is always center aligned vertically instead of top align

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**Describe the bug**

Earlier Guake used to be always top aligned. With the new version, it seems to be center aligned vertically and there seems to be no way to change this behavior.

**Expected behavior**

Guake should be top align by default.

**Actual behavior**

Guake is center aligned


**To Reproduce**

Run Guake 3.11.dev0

Make the height slider slightly smaller so as to not let Guake occupy the whole screen


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Please run `$ guake --support`, and paste the results here. Don't put backticks (`` ` ``) around it! The output already contains Markdown formatting. And make sure you run the command **OUTSIDE** the Guake.

x guake --support [☸ eks-pt (mec)]

(guake:175112): Gtk-WARNING **: 10:41:36.975: Theme parsing error: gtk-dark.css:5890:26: '-shadow' is not a valid color name

(guake:175112): Gtk-WARNING **: 10:41:36.975: Theme parsing error: gtk-dark.css:5893:14: not a number

(guake:175112): Gtk-WARNING **: 10:41:36.975: Theme parsing error: gtk-dark.css:5894:13: not a number

(guake:175112): Gtk-WARNING **: 10:41:36.975: Theme parsing error: gtk-dark.css:5895:11: Expected a length
$ guake --support

Guake Version: 3.11.dev0

Vte Version: 0.72.1

Vte Runtime Version: 0.72.1

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GTK+ Version: 3.24.37

GDK Backend: