Low resolution of rendered pictures

**Steps to reproduce**
Call v2/indigo/render in remote mode with (options, struct):

options: {
aromatize-skip-superatoms: true,
gross-formula-add-rsites: true,
ignore-stereochemistry-errors: true,
mass-skip-error-on-pseudoatoms: false,
render-output-format: "png",
smart-layout: true
},
struct: {}
[struct.txt.zip](https://github.com/epam/Indigo/files/8177268/struct.txt.zip)

**Expected result**
Image in resolution, applicable to use in further (for example, in MS Word or MS PowerPoint)

**Actual result**
Image has very low resolution, it is not applicable for further use