Proper sorting of available ecoinvent versions

[marc-vdm]

DO NOT MERGE THIS BEFORE ECOINVENT 3.10 IS SUPPORTED IN AB

• Resolve Sort available ecoinvent databases based on number instead of as str #1140

Checklist

• Keep pull requests small so they can be easily reviewed.
• Categorize the PR by setting a good title and adding one of the labels:
  bug, feature, ui, change, documentation, breaking, ci
  as they show up in the changelog
• Link this PR to related issues by using closing keywords.
• Request a review from another developer.
• Add milestone once ei 3.10 is supported in AB

[coveralls]

coverage: 50.029% (-0.004%) from 50.033%
when pulling 897cc2c on marc-vdm:ecoinvent_version_sort
into fe69950 on LCA-ActivityBrowser:master.

[marc-vdm]

Closing in favour of developments for #1142