Updating tools/pretext/pretext_graph from 0.0.6 to 0.0.7

[Smeds]

FOR CONTRIBUTOR:

• I have read the CONTRIBUTING.md document and this tool is appropriate for the tools-iuc repo.
• License permits unrestricted use (educational + commercial)
• This PR adds a new tool or tool collection
• This PR updates an existing tool or tool collection
• This PR does something else (explain below)

[bernt-matthias]

Wondering why the release is marked as pre-release https://github.com/sanger-tol/PretextGraph/releases

[Delphine-L]

I am not sure why it's in prerelease, but they updated the conda recipe and the new version is fixing a lot of annoying bugs. So I would be in favor to merge it anyway.