[BUG] Sizing mode example layout broken in docs

[bryevdv]

ref: https://docs.bokeh.org/en/latest/docs/user_guide/layout.html#sizing-modes

Starting in 2.3 the layout of the examples above is broken:

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cc @mattpap

[philippjfr]

Saw a similar case yesterday, with a number of plots overlapping. Definitely something off about stretch_height/stretch_both.

[philippjfr]

@mattpap You sure this issue is limited to the docs? I think this is another layout regression. Will try to come up with a standalone example tomorrow.

[mattpap]

@philippjfr, it is a layout regression, that's why I removed docs label. I'm working on fix.

[philippjfr]

Oh I'm blind, "removed". Sorry for the noise.