feat: add configurable maxBuffer option to runDiffImageToSnapshot

[haze]

Description

Adds a new option maxChildProcessBufferSizeInBytes. This lets us override the maximum allowed byte count for stderr/stdout for diff-screenshot child processes.

Motivation and Context

One of my projects routinely diffs large (>4k) images. The default 10 MB limit is too small for my use case.

How Has This Been Tested?

Privately tested in a fork before upstreaming changes; Configuration change means we no longer run into the default limit. Updated tests.

Types of Changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] Documentation (adding or updating documentation)
• [ ] Dependency update

Checklist:

• [x] My change requires a change to the documentation and I have updated the documentation accordingly.
• [x] My changes are in sync with the code style of this project.
• [x] There aren't any other open Pull Requests for the same issue/update.
• [x] These changes should be applied to a maintenance branch.
• [x] I have added the Apache 2.0 license header to any new files created.

What is the Impact to Developers Using Jest-Image-Snapshot?

There should be no discernible impact beyond additional configurability.

[dogpatch626]

Will need updates to readme

[oneamexbot]

:tada: This PR is included in version 6.4.0 :tada:

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot :package::rocket: