Update dscanner commit hash to include AliasAssign detection

[RazvanN7]

I also disabled the newly added check for unused function return values because it had hundreds of failures. The check was added in August 2020, whereas phobos was using a version of dscanner from February 2020.

[dlang-bot]

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[kinke]

Wrt. the dscanner crash, see dlang-community/D-Scanner#823 (comment).

[RazvanN7]

Thanks @kinke . I will try to revert dlang-community/libddoc#44

[ibuclaw]

(Forcing restart of Azure pipelines).

[RazvanN7]

@thewilsonator I think this is ready to go so I'm gonna go ahead and merge this.