Conditionally fetch mutation assessor download data

[onursumer]

Related to cBioPortal/cbioportal#9104

We still need to update the show.genomenexus.annotation_sources property in the backend to make this change effective.

Checks

• Has tests or has a separate issue that describes the types of test that should be created. If no test is included it should explicitly be mentioned in the PR why there is no test.
• The commit log is comprehensible. It follows 7 rules of great commit messages. For most PRs a single commit should suffice, in some cases multiple topical commits can be useful. During review it is ok to see tiny commits (e.g. Fix reviewer comments), but right before the code gets merged to master or rc branch, any such commits should be squashed since they are useless to the other developers. Definitely avoid merge commits, use rebase instead.
• Is this PR adding logic based on one or more clinical attributes? If yes, please make sure validation for this attribute is also present in the data validation / data loading layers (in backend repo) and documented in File-Formats Clinical data section!

[leexgh]

Thanks! Not sure should we also disable it on mutation table to be consistent?

[leexgh]

I've also disabled mutation assessor on genome nexus too, we should find a good way to handle this unstableness

[onursumer]

Thanks! Not sure should we also disable it on mutation table to be consistent?

@leexgh Seems like we already conditionally show/hide it in the mutation table using the same config prop:

cbioportal-frontend/src/shared/components/mutationTable/column/FunctionalImpactColumnFormatter.tsx

Line 63 in 6211c30

const showMutationAssessor = shouldShowMutationAssessor();

It should be disabled when we set the corresponding prop, right?

[leexgh]

@onursumer Oh I forgot we already have this, then it's fine I guess. Do we want to have another pr to disable mutation assessor?