Issue Colorbar placement

Hello,

I am using Plots with PyPlot as a backend for `heatmap`. The placement of the colorbar doesn't match the width of the heatmap (see picture) also I can't move the position of the colorbar.
The first issue is resolved when I switch to GR as a backend but not the second.

Here is the same issue https://github.com/JuliaPlots/Plots.jl/issues/1755

Here is my code:

```
using Plots
pyplot()

x = randn(10,200)
heatmap(x, color = :inferno, colorbar = :bottom)
```

Result:
[picture.pdf](https://github.com/JuliaPy/PyPlot.jl/files/4660040/picture.pdf)