Macbook Pro 2018 13 inch Partition Won't Delete
I suppose your System is High Sierra or Mojave.
I'm amazed that Boot Camp Assistant created a container during its installation.
Otherwise, to remove this container, the terminal command is:
diskutil ap deletecontainer disk1 

Then to free disk space :
diskutil erasevolume free space disk0s3

and finally add this space to your system container :
diskutil ap resizecontainer disk2 0b

After these operations, give the result of :
diskutil list

There is a partition that seems useless to me:
4: Apple_Boot Boot OS X 134.2 MB disk0s4

Before removing it, are you using Filevault (data encryption)?
Edit : Filevault don't need this partition type. I've try on a Virtual Machine.
You can delete this partition :
diskutil erasevolume free space disk0s4 

Then add this space to your system container :
diskutil ap resizecontainer disk2 0b