chore: add import sort order to eslint

[DNR500]

Jira: LF-7839

First attempt was using the eslint-plugin-simple-import-sort package. It did autofix but main issues where..

• alphabetically sorting - doesn't factor in capitalisation like how we wanted. It is built with the intention of case insensitive sorting and can't be configured to do otherwise.
• Any import that doesn't output a variable as part of the import statement will be moved to the top, this isn't great as sometimes importing code like this can have side effects where import order matters

The end solution using a mix of sort-imports and eslint-plugin-import
This PR is using a mix of eslints built in sort-imports and the eslint-plugin-import that we already have in the codebase. sort-import handles the sorting of named imports and the plugin does the rest. Also import statements without variable assignment are ignored. It should autofix imports too.

[DNR500]

Closing this PR as have switched to looking at prettier as an option - see #238